System.Char Structure

Summary

Represents a Unicode character.

C# Syntax:

[Serializable] public struct Char : IComparable, IConvertible

This type is safe for multithreaded operations.

The Char value type represents Unicode characters with values ranging from hexadecimal 0x0000 to 0xFFFF.

Char provides methods to compare instances of this type, convert the value of an instance to its string representation, convert the string representation of a number to an instance of this type, and determine whether an instance is in a category such as digit, letter, punctuation, control character, and so on.

For information about how format specification codes control the string representation of value types, see the conceptual topic at MSDN: formattingoverview.

For more information about Unicode, see the Unicode Standard at http://www.unicode.org.

This type implements interfaces IComparable and IConvertible. Use the Convert class for conversions instead of this type's explicit interface member implementation of IConvertible.

The following sample demonstrates some of the methods in Char.

using System;

public class CharStructureSample {
	public static void Main() {
		char chA = 'A';
		char ch1 = '1';
		string str = "test string"; 

		Console.WriteLine(chA.CompareTo('B'));			// Output: "-1" (meaning 'A' is 1 less than 'B')
		Console.WriteLine(chA.Equals('A'));				// Output: "True"
		Console.WriteLine(Char.GetNumericValue(ch1));	// Output: "1"
		Console.WriteLine(Char.IsControl('\t'));		// Output: "True"
		Console.WriteLine(Char.IsDigit(ch1));			// Output: "True"
		Console.WriteLine(Char.IsLetter(','));			// Output: "False"
		Console.WriteLine(Char.IsLower('u'));			// Output: "True"
		Console.WriteLine(Char.IsNumber(ch1));			// Output: "True"
		Console.WriteLine(Char.IsPunctuation('.'));		// Output: "True"
		Console.WriteLine(Char.IsSeparator(str, 4));	// Output: "True"
		Console.WriteLine(Char.IsSymbol('+'));			// Output: "True"
		Console.WriteLine(Char.IsWhiteSpace(str, 4));	// Output: "True"
		Console.WriteLine(Char.Parse("S"));				// Output: "S"
		Console.WriteLine(Char.ToLower('M'));			// Output: "m"
		Console.WriteLine('x'.ToString());				// Output: "x"
	}
}

    

System Namespace | IComparable | IConvertible | String

System.Char Member List:

Public Fields

MaxValue	Represents the largest possible value of a Char. This field is constant.
MinValue	Represents the smallest possible value of a Char. This field is constant.

Public Methods

CompareTo	Compares this instance to a specified object and returns an indication of their relative values.
Equals	Overridden: Returns a value indicating whether this instance is equal to a specified object.
GetHashCode	Overridden: Returns the hash code for this instance.
GetNumericValue	Overloaded: GetNumericValue(char c) Converts the specified numeric Unicode character to a double-precision floating point number.
GetNumericValue	Overloaded: GetNumericValue(string s, int index) Converts the numeric Unicode character at the specified position in a specified string to a double-precision floating point number.
GetType (inherited from System.Object)	See base class member description: System.Object.GetType Derived from System.Object, the primary base class for all objects.
GetTypeCode	Returns the TypeCode for value type Char.
GetUnicodeCategory	Overloaded: GetUnicodeCategory(char c) Categorizes a specified Unicode character into a group identified by one of the UnicodeCategory values.
GetUnicodeCategory	Overloaded: GetUnicodeCategory(string s, int index) Categorizes the character at the specified position in a specified string into a group identified by one of the UnicodeCategory values.
IsControl	Overloaded: IsControl(char c) Indicates whether the specified Unicode character is categorized as a control character.
IsControl	Overloaded: IsControl(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a control character.
IsDigit	Overloaded: IsDigit(char c) Indicates whether the specified Unicode character is categorized as a decimal digit.
IsDigit	Overloaded: IsDigit(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a decimal digit.
IsLetter	Overloaded: IsLetter(char c) Indicates whether the specified Unicode character is categorized as an alphabetic letter.
IsLetter	Overloaded: IsLetter(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as an alphabetic character.
IsLetterOrDigit	Overloaded: IsLetterOrDigit(char c) Indicates whether the specified Unicode character is categorized as an alphabetic letter or a decimal digit.
IsLetterOrDigit	Overloaded: IsLetterOrDigit(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as an alphabetic character or a decimal digit.
IsLower	Overloaded: IsLower(char c) Indicates whether the specified Unicode character is categorized as a lowercase letter.
IsLower	Overloaded: IsLower(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a lowercase letter.
IsNumber	Overloaded: IsNumber(char c) Indicates whether the specified Unicode character is categorized as a decimal digit or hexadecimal number.
IsNumber	Overloaded: IsNumber(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a decimal digit or hexadecimal number.
IsPunctuation	Overloaded: IsPunctuation(char c) Indicates whether the specified Unicode character is categorized as a punctuation mark.
IsPunctuation	Overloaded: IsPunctuation(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a punctuation mark.
IsSeparator	Overloaded: IsSeparator(char c) Indicates whether the specified Unicode character is categorized as a separator character.
IsSeparator	Overloaded: IsSeparator(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a separator character.
IsSurrogate	Overloaded: IsSurrogate(char c) Indicates whether the specified Unicode character is categorized as a surrogate character.
IsSurrogate	Overloaded: IsSurrogate(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a surrogate character.
IsSymbol	Overloaded: IsSymbol(char c) Indicates whether the specified Unicode character is categorized as a symbol character.
IsSymbol	Overloaded: IsSymbol(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as a symbol character.
IsUpper	Overloaded: IsUpper(char c) Indicates whether the specified Unicode character is categorized as an uppercase letter.
IsUpper	Overloaded: IsUpper(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as an uppercase letter.
IsWhiteSpace	Overloaded: IsWhiteSpace(char c) Indicates whether the specified Unicode character is categorized as white space.
IsWhiteSpace	Overloaded: IsWhiteSpace(string s, int index) Indicates whether the character at the specified position in a specified string is categorized as white space.
Parse	Converts the value of the specified string to its equivalent Unicode character.
ToLower	Overloaded: ToLower(char c) Converts the value of a Unicode character to its lowercase equivalent.
ToLower	Overloaded: ToLower(char c, CultureInfo culture) Converts the value of a specified Unicode character to its lowercase equivalent using specified culture-specific formatting information.
ToString	Overloaded: ToString() Overridden: Converts the value of this instance to its equivalent string representation.
ToString	Overloaded: ToString(char c) Converts the specified Unicode character to its equivalent string representation.
ToString	Overloaded: ToString(IFormatProvider provider) Converts the value of this instance to its equivalent string representation using the specified culture-specific format information.
ToUpper	Overloaded: ToUpper(char c) Converts the value of a Unicode character to its uppercase equivalent.
ToUpper	Overloaded: ToUpper(char c, CultureInfo culture) Converts the value of a specified Unicode character to its uppercase equivalent using specified culture-specific formatting information.

Protected Methods

Finalize (inherited from System.Object)	See base class member description: System.Object.Finalize Derived from System.Object, the primary base class for all objects.
MemberwiseClone (inherited from System.Object)	See base class member description: System.Object.MemberwiseClone Derived from System.Object, the primary base class for all objects.

Hierarchy:

• System.Object
• System.ValueType
• System.Char

System.Char Member Details

Summary

Represents the largest possible value of a Char. This field is constant.

C# Syntax:

public const char MaxValue;

The value of this constant is hexadecimal 0xFFFF.

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Summary

Represents the smallest possible value of a Char. This field is constant.

C# Syntax:

public const char MinValue;

The value of this constant is hexadecimal 0x00.

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Summary

Compares this instance to a specified object and returns an indication of their relative values.

C# Syntax:

public int CompareTo(    object value );

value

An object to compare, or null.

Return Value:

A signed number indicating the relative values of this instance and value.

Return Value	Description
Less than zero	This instance is less than .
Zero	This instance is equal to .
Greater than zero	This instance is greater than value. -or- value is null.

Exceptions

Exception Type	Condition
ArgumentException	value is not a Char or null.

Any instance of Char, regardless of its value, is considered greater than null.

value must be null or an instance of Char; otherwise, an exception is thrown.

The comparison performed by this method is based on the encoded values of this instance and value, not necessarily their lexicographical characteristics.

This method is implemented to support the IComparable interface.

The following sample demonstrates Char.CompareTo.

using System;

public class CompareToSample {
	public static void Main() {
		char chA = 'A';
		char chB = 'B';

		Console.WriteLine(chA.CompareTo('A'));	// Output: "0" (meaning they're equal)
		Console.WriteLine('b'.CompareTo(chB));	// Output: "32" (meaning 'b' is greater than 'B' by 32)
		Console.WriteLine(chA.CompareTo(chB));	// Output: "-1" (meaning 'A' is less than 'B' by 1)
	}
}

    

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Summary

Returns a value indicating whether this instance is equal to a specified object.

C# Syntax:

public override bool Equals(    object obj );

obj

An object to compare with this instance or null.

Return Value:

true if obj is an instance of Char and equals the value of this instance; otherwise, false.

The comparison performed by this method is based on the encoded values of this instance and obj, not necessarily their lexicographical characteristics.

The following sample demonstrates Char.Equals.

using System;

public class EqualsSample {
	public static void Main() {
		char chA = 'A';
		char chB = 'B';

		Console.WriteLine(chA.Equals('A'));		// Output: "True"
		Console.WriteLine('b'.Equals(chB));		// Output: "False"
	}
}

    

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Inherited
See base class member description: System.Object.Finalize

C# Syntax:

~Char();

For more information on members inherited from System.Object click on the link above.

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Summary

Returns the hash code for this instance.

C# Syntax:

public override int GetHashCode();

Return Value:

A 32-bit signed integer hash code.

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Summary

Converts the specified numeric Unicode character to a double-precision floating point number.

C# Syntax:

public static double GetNumericValue(    char c );

c

A Unicode character.

Return Value:

The numeric value of c if that character represents a number; otherwise, -1.0.

For example, if c is '5', the return value is 5. However, if c is 'z', the return value is -1.

A character has an associated numeric value if and only if it is a member of one of the following categories in UnicodeCategory: DecimalDigitNumber, LetterNumber, or OtherNumber.

The following sample demonstrates Char.GetNumericValue.

using System;

public class GetNumericValueSample {
	public static void Main() {
		string str = "input: 1";

		Console.WriteLine(Char.GetNumericValue('8'));		// Output: "8"
		Console.WriteLine(Char.GetNumericValue(str, 8));	// Output: "1"
	}
}

    

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Summary

Converts the numeric Unicode character at the specified position in a specified string to a double-precision floating point number.

C# Syntax:

public static double GetNumericValue(    string s,    int index );

s

A String.

index

The character position in s.

Return Value:

The numeric value of the character at position index in s if that character represents a number; otherwise, -1.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

For example, if the character at position index in s is '5', the return value is 5. However, if the character at position index in s is 'z', the return value is -1.

Character positions in a string are indexed starting from zero.

A character has an associated numeric value if and only if it is a member of one of the following categories in UnicodeCategory: DecimalDigitNumber, LetterNumber, or OtherNumber.

The following sample demonstrates Char.GetNumericValue.

using System;

public class GetNumericValueSample {
	public static void Main() {
		string str = "input: 1";

		Console.WriteLine(Char.GetNumericValue('8'));		// Output: "8"
		Console.WriteLine(Char.GetNumericValue(str, 8));	// Output: "1"
	}
}

    

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Inherited
See base class member description: System.Object.GetType

C# Syntax:

public Type GetType();

For more information on members inherited from System.Object click on the link above.

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Summary

Returns the TypeCode for value type Char.

C# Syntax:

public TypeCode GetTypeCode();

Return Value:

The enumerated constant, TypeCode.Char.

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Summary

Categorizes a specified Unicode character into a group identified by one of the UnicodeCategory values.

C# Syntax:

public static UnicodeCategory GetUnicodeCategory(    char c );

c

A Unicode character.

Return Value:

A UnicodeCategory value that identifies the group that contains c.

The following sample demonstrates Char.GetUnicodeCategory.

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Summary

Categorizes the character at the specified position in a specified string into a group identified by one of the UnicodeCategory values.

C# Syntax:

public static UnicodeCategory GetUnicodeCategory(    string s,    int index );

s

A String.

index

The character position in s.

Return Value:

A UnicodeCategory enumerated constant that identifies the group that contains the character at position index in s.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

The following sample demonstrates Char.GetUnicodeCategory.

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Summary

Indicates whether the specified Unicode character is categorized as a control character.

C# Syntax:

public static bool IsControl(    char c );

c

A Unicode character.

Return Value:

true if c is a control character; otherwise, false.

Valid control characters are members of the following category in UnicodeCategory: Control.

The following sample demonstrates Char.IsControl.

using System;

public class IsControlSample {
	public static void Main() {
		string str = "sample string";

		Console.WriteLine(Char.IsControl('\t'));	// Output: "True"
		Console.WriteLine(Char.IsControl(str, 7));	// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a control character.

C# Syntax:

public static bool IsControl(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a control character; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid control characters are members of the following category in UnicodeCategory: Control.

The following sample demonstrates Char.IsControl.

using System;

public class IsControlSample {
	public static void Main() {
		string str = "sample string";

		Console.WriteLine(Char.IsControl('\t'));	// Output: "True"
		Console.WriteLine(Char.IsControl(str, 7));	// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a decimal digit.

C# Syntax:

public static bool IsDigit(    char c );

c

A Unicode character.

Return Value:

true if c is a decimal digit; otherwise, false.

This method determines if a Char is a radix-10 digit. This contrasts with Char.IsNumber which determines if a Char is of any numeric Unicode category.

Valid digits are members of the following category in UnicodeCategory: DecimalDigitNumber.

The following sample demonstrates Char.IsDigit.

using System;

public class IsDigitSample {
	public static void Main() {
		char ch = '8';

		Console.WriteLine(Char.IsDigit(ch));					// Output: "True"
		Console.WriteLine(Char.IsDigit("sample string", 7));	// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a decimal digit.

C# Syntax:

public static bool IsDigit(    string s,    int index );

s

A String.

index

The character position in s.

Return Value:

true if the character at position index in s is a decimal digit; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

This method determines if a Char is a radix-10 digit. This contrasts with Char.IsNumber, which determines if a Char is of any numeric Unicode category.

Character positions in a string are indexed starting from zero.

Valid digits are members of the following category in UnicodeCategory: DecimalDigitNumber.

The following sample demonstrates Char.IsDigit.

using System;

public class IsDigitSample {
	public static void Main() {
		char ch = '8';

		Console.WriteLine(Char.IsDigit(ch));					// Output: "True"
		Console.WriteLine(Char.IsDigit("sample string", 7));	// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as an alphabetic letter.

C# Syntax:

public static bool IsLetter(    char c );

c

A Unicode character.

Return Value:

true if c is an alphabetic letter; otherwise, false.

Valid letters are members of the following categories in UnicodeCategory: UppercaseLetter, LowercaseLetter, TitlecaseLetter, ModifierLetter, and OtherLetter.

The following sample demonstrates Char.IsLetter.

using System;

public class IsLetterSample {
	public static void Main() {
		char ch = '8';

		Console.WriteLine(Char.IsLetter(ch));					// False
		Console.WriteLine(Char.IsLetter("sample string", 7));	// True
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as an alphabetic character.

C# Syntax:

public static bool IsLetter(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is an alphabetic character; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid letters are members of the following categories in UnicodeCategory: UppercaseLetter, LowercaseLetter, TitlecaseLetter, ModifierLetter, and OtherLetter.

The following sample demonstrates Char.IsLetter.

using System;

public class IsLetterSample {
	public static void Main() {
		char ch = '8';

		Console.WriteLine(Char.IsLetter(ch));					// False
		Console.WriteLine(Char.IsLetter("sample string", 7));	// True
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as an alphabetic letter or a decimal digit.

C# Syntax:

public static bool IsLetterOrDigit(    char c );

c

A Unicode character.

Return Value:

true if c is an alphabetic letter or a decimal digit; otherwise, false.

Valid alphabetic letters and decimal digits are members of the following categories in UnicodeCategory: UppercaseLetter, LowercaseLetter, TitlecaseLetter, ModifierLetter, OtherLetter, or DecimalDigitNumber.

The following sample demonstrates Char.IsLetterOrDigit.

using System;

public class IsLetterOrDigitSample {
	public static void Main() {
		string str = "newline:\n";

		Console.WriteLine(Char.IsLetterOrDigit('8'));		// Output: "True"
		Console.WriteLine(Char.IsLetterOrDigit(str, 8));	// Output: "False", because it's a newline
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as an alphabetic character or a decimal digit.

C# Syntax:

public static bool IsLetterOrDigit(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is an alphabetic character or a decimal digit; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid alphabetic letters and decimal digits are members of the following categories in UnicodeCategory: UppercaseLetter, LowercaseLetter, TitlecaseLetter, ModifierLetter, OtherLetter, or DecimalDigitNumber.

The following sample demonstrates Char.IsLetterOrDigit.

using System;

public class IsLetterOrDigitSample {
	public static void Main() {
		string str = "newline:\n";

		Console.WriteLine(Char.IsLetterOrDigit('8'));		// Output: "True"
		Console.WriteLine(Char.IsLetterOrDigit(str, 8));	// Output: "False", because it's a newline
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a lowercase letter.

C# Syntax:

public static bool IsLower(    char c );

c

A Unicode character.

Return Value:

true if c is a lowercase letter; otherwise, false.

Valid lowercase letters are members of the following category in UnicodeCategory: LowercaseLetter.

The following sample demonstrates Char.IsLower.

using System;

public class IsLowerSample {
	public static void Main() {
		char ch = 'a';

		Console.WriteLine(Char.IsLower(ch));				// Output: "True"
		Console.WriteLine(Char.IsLower("upperCase", 5));	// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a lowercase letter.

C# Syntax:

public static bool IsLower(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a lowercase letter; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid lowercase letters are members of the following category in UnicodeCategory: LowercaseLetter.

The following sample demonstrates Char.IsLower.

using System;

public class IsLowerSample {
	public static void Main() {
		char ch = 'a';

		Console.WriteLine(Char.IsLower(ch));				// Output: "True"
		Console.WriteLine(Char.IsLower("upperCase", 5));	// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a decimal digit or hexadecimal number.

C# Syntax:

public static bool IsNumber(    char c );

c

A Unicode character.

Return Value:

true if c is a decimal digit or hexadecimal number; otherwise, false.

This method determines if a Char is of any numeric Unicode category. This contrasts with Char.IsDigit, which determines if a Char is a radix-10 digit.

Valid numbers are members of the following categories in UnicodeCategory: DecimalDigitNumber, LetterNumber, or OtherNumber.

The following sample demonstrates Char.IsNumber.

using System;

public class IsNumberSample {
	public static void Main() {
		string str = "non-numeric";

		Console.WriteLine(Char.IsNumber('8'));		// Output: "True"
		Console.WriteLine(Char.IsNumber(str, 3));	// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a decimal digit or hexadecimal number.

C# Syntax:

public static bool IsNumber(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a decimal digit or hexadecimal number; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

This method determines if a Char is of any numeric Unicode category. This contrasts with Char.IsDigit, which determines if a Char is a radix-10 digit.

Character positions in a string are indexed starting from zero.

Valid numbers are members of the following categories in UnicodeCategory: DecimalDigitNumber, LetterNumber, or OtherNumber.

The following sample demonstrates Char.IsNumber.

using System;

public class IsNumberSample {
	public static void Main() {
		string str = "non-numeric";

		Console.WriteLine(Char.IsNumber('8'));		// Output: "True"
		Console.WriteLine(Char.IsNumber(str, 3));	// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a punctuation mark.

C# Syntax:

public static bool IsPunctuation(    char c );

c

A Unicode character.

Return Value:

true if c is a punctuation mark; otherwise, false.

Valid punctuation marks are members of the following categories in UnicodeCategory: ConnectorPunctuation, DashPunctuation, OpenPunctuation, ClosePunctuation, InititalQuotePunctuation, FinalQuotePunctuation, or OtherPunctuation.

The following sample demonstrates Char.IsPunctuation.

using System;

public class IsPunctuationSample {
	public static void Main() {
		char ch = '.';

		Console.WriteLine(Char.IsPunctuation(ch));						// Output: "True"
		Console.WriteLine(Char.IsPunctuation("no punctuation", 3));		// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a punctuation mark.

C# Syntax:

public static bool IsPunctuation(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a punctuation mark; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid punctuation marks are members of the following categories in UnicodeCategory: ConnectorPunctuation, DashPunctuation, OpenPunctuation, ClosePunctuation, InititalQuotePunctuation, FinalQuotePunctuation, or OtherPunctuation.

The following sample demonstrates Char.IsPunctuation.

using System;

public class IsPunctuationSample {
	public static void Main() {
		char ch = '.';

		Console.WriteLine(Char.IsPunctuation(ch));						// Output: "True"
		Console.WriteLine(Char.IsPunctuation("no punctuation", 3));		// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a separator character.

C# Syntax:

public static bool IsSeparator(    char c );

c

A Unicode character.

Return Value:

true if c is a separator character; otherwise, false.

Valid separator characters are members of the following categories in UnicodeCategory: SpaceSeparator, LineSeparator, or ParagraphSeparator.

The following sample demonstrates Char.IsSeparator.

using System;

public class IsSeparatorSample {
	public static void Main() {
		string str = "twain1 twain2";

		Console.WriteLine(Char.IsSeparator('a'));		// Output: "False"
		Console.WriteLine(Char.IsSeparator(str, 6));	// Output: "True"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a separator character.

C# Syntax:

public static bool IsSeparator(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a separator character; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid separator characters are members of the following categories in UnicodeCategory: SpaceSeparator, LineSeparator, or ParagraphSeparator.

The following sample demonstrates Char.IsSeparator.

using System;

public class IsSeparatorSample {
	public static void Main() {
		string str = "twain1 twain2";

		Console.WriteLine(Char.IsSeparator('a'));		// Output: "False"
		Console.WriteLine(Char.IsSeparator(str, 6));	// Output: "True"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a surrogate character.

C# Syntax:

public static bool IsSurrogate(    char c );

c

A Unicode character.

Return Value:

true if c is a surrogate character; otherwise, false.

Valid surrogate characters are members of the following category in UnicodeCategory: Surrogate.

For more information about surrogate pairs, see the Unicode Standard at http://www.unicode.org.

The following sample demonstrates Char.IsSurrogate.

using System;

public class IsSurrogateSample {
	public static void Main() {
		string str = "\U00010F00"; // Unicode values between 0x10000 and 0x10FFF are represented by two 16-bit "surrogate" characters

		Console.WriteLine(Char.IsSurrogate('a'));		// Output: "False"
		Console.WriteLine(Char.IsSurrogate(str, 0));	// Output: "True"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a surrogate character.

C# Syntax:

public static bool IsSurrogate(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a surrogate character; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid surrogate characters are members of the following category in UnicodeCategory: Surrogate.

For more information about surrogate pairs, see the Unicode Standard at http://www.unicode.org.

The following sample demonstrates Char.IsSurrogate.

using System;

public class IsSurrogateSample {
	public static void Main() {
		string str = "\U00010F00"; // Unicode values between 0x10000 and 0x10FFF are represented by two 16-bit "surrogate" characters

		Console.WriteLine(Char.IsSurrogate('a'));		// Output: "False"
		Console.WriteLine(Char.IsSurrogate(str, 0));	// Output: "True"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as a symbol character.

C# Syntax:

public static bool IsSymbol(    char c );

c

A Unicode character.

Return Value:

true if c is a symbol character; otherwise, false.

Valid symbols are members of the following categories in UnicodeCategory: MathSymbol, CurrencySymbol, ModifierSymbol, and OtherSymbol.

The following sample demonstrates Char.IsSymbol.

using System;

public class IsSymbolSample {
	public static void Main() {
		string str = "non-symbolic characters"; 

		Console.WriteLine(Char.IsSymbol('+'));		// Output: "True"
		Console.WriteLine(Char.IsSymbol(str, 8));	// Output: "False"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as a symbol character.

C# Syntax:

public static bool IsSymbol(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is a symbol character; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid symbols are members of the following categories in UnicodeCategory: MathSymbol, CurrencySymbol, ModifierSymbol, and OtherSymbol.

The following sample demonstrates Char.IsSymbol.

using System;

public class IsSymbolSample {
	public static void Main() {
		string str = "non-symbolic characters"; 

		Console.WriteLine(Char.IsSymbol('+'));		// Output: "True"
		Console.WriteLine(Char.IsSymbol(str, 8));	// Output: "False"
	}
}

    

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Summary

Indicates whether the specified Unicode character is categorized as an uppercase letter.

C# Syntax:

public static bool IsUpper(    char c );

c

A Unicode character.

Return Value:

true if c is an uppercase letter; otherwise, false.

Valid uppercase letters are members of the following category in UnicodeCategory: UppercaseLetter.

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Summary

Indicates whether the character at the specified position in a specified string is categorized as an uppercase letter.

C# Syntax:

public static bool IsUpper(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is an uppercase letter; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid uppercase letters are members of the following category in UnicodeCategory: UppercaseLetter.

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Summary

Indicates whether the specified Unicode character is categorized as white space.

C# Syntax:

public static bool IsWhiteSpace(    char c );

c

A Unicode character.

Return Value:

true if c is white space; otherwise, false.

Valid white space characters are members of the SpaceSeparator category in UnicodeCategory, as well as these Unicode characters: hexadecimal 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x0085, 0x2028, and 0x2029.

The following sample demonstrates Char.IsWhiteSpace.

using System;

public class IsWhiteSpaceSample {
	public static void Main() {
		string str = "black matter"; 

		Console.WriteLine(Char.IsWhiteSpace('A'));		// Output: "False"
		Console.WriteLine(Char.IsWhiteSpace(str, 5));	// Output: "True"
	}
}

    

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Summary

Indicates whether the character at the specified position in a specified string is categorized as white space.

C# Syntax:

public static bool IsWhiteSpace(    string s,    int index );

s

A string.

index

The character position in s.

Return Value:

true if the character at position index in s is white space; otherwise, false.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
ArgumentOutOfRangeException	index is less than zero or greater than the last position in s.

Character positions in a string are indexed starting from zero.

Valid white space characters are members of the SpaceSeparator category in UnicodeCategory, as well as these Unicode characters: hexadecimal 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x0085, 0x2028, and 0x2029.

The following sample demonstrates Char.IsWhiteSpace.

using System;

public class IsWhiteSpaceSample {
	public static void Main() {
		string str = "black matter"; 

		Console.WriteLine(Char.IsWhiteSpace('A'));		// Output: "False"
		Console.WriteLine(Char.IsWhiteSpace(str, 5));	// Output: "True"
	}
}

    

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Inherited
See base class member description: System.Object.MemberwiseClone

C# Syntax:

protected object MemberwiseClone();

For more information on members inherited from System.Object click on the link above.

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Summary

Converts the value of the specified string to its equivalent Unicode character.

C# Syntax:

public static char Parse(    string s );

s

A string containinga single character or null.

Return Value:

A Unicode character equivalent to the sole character in s.

Exceptions

Exception Type	Condition
ArgumentNullException	s is null.
FormatException	s contains more than one character.

The following sample demonstrates Char.Parse.

using System;

public class ParseSample {
	public static void Main() {
		Console.WriteLine(Char.Parse("A")); // Output: 'A'
	}
}

    

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Summary

Converts the value of a Unicode character to its lowercase equivalent.

C# Syntax:

public static char ToLower(    char c );

c

A Unicode character.

Return Value:

The lowercase equivalent of c.

-or-

The unchanged value of c, if c is already lowercase or not alphabetic.

Formatting information is obtained from the current culture.

Use String.ToLower to convert a string to lowercase.

The following sample demonstrates Char.ToLower.

using System;
using System.Globalization;  // for CultureInfo

public class ToLowerSample {
	public static void Main() {
		Console.WriteLine(Char.ToLower('A'));				// Output: "a"
	}
}

    

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Summary

Converts the value of a specified Unicode character to its lowercase equivalent using specified culture-specific formatting information.

C# Syntax:

public static char ToLower(    char c,    CultureInfo culture );

c

A Unicode character.

culture

A CultureInfo object that supplies culture-specific formatting information, or null.

Return Value:

The lowercase equivalent of c, formatted according to culture.

-or-

The unchanged value of c, if c is already lowercase or not alphabetic.

Exceptions

Exception Type	Condition
ArgumentNullException	culture is null.

Use String.ToLower to convert a string to lowercase.

The following sample demonstrates Char.ToLower.

using System;
using System.Globalization;  // for CultureInfo

public class ToLowerSample {
	public static void Main() {
		Console.WriteLine(Char.ToLower('A'));				// Output: "a"
	}
}

    

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Summary

Converts the value of this instance to its equivalent string representation.

C# Syntax:

public override string ToString();

Return Value:

The string representation of the value of this instance.

The following sample demonstrates Char.ToString.

using System;

public class ToStringSample {
	public static void Main() {
		char ch = 'a';
		Console.WriteLine(ch.ToString());		// Output: "a"

		Console.WriteLine(Char.ToString('b'));	// Output: "b"
	}
}

    

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Summary

Converts the specified Unicode character to its equivalent string representation.

C# Syntax:

public static string ToString(    char c );

c

A Unicode character.

Return Value:

The string representation of the value of c.

The following sample demonstrates Char.ToString.

using System;

public class ToStringSample {
	public static void Main() {
		char ch = 'a';
		Console.WriteLine(ch.ToString());		// Output: "a"

		Console.WriteLine(Char.ToString('b'));	// Output: "b"
	}
}

    

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Summary

Converts the value of this instance to its equivalent string representation using the specified culture-specific format information.

C# Syntax:

public string ToString(    IFormatProvider provider );

provider

(Reserved) An IFormatProvider that supplies culture-specific formatting information.

Return Value:

The string representation of the value of this instance as specified by provider.

The provider parameter is ignored; it does not participate in this operation.

The following sample demonstrates an overload of Char.ToString.

using System;

public class ToStringSample {
	public static void Main() {
		char ch = 'a';
		Console.WriteLine(ch.ToString());		// Output: "a"

		Console.WriteLine(Char.ToString('b'));	// Output: "b"
	}
}

    

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Summary

Converts the value of a Unicode character to its uppercase equivalent.

C# Syntax:

public static char ToUpper(    char c );

c

A Unicode character.

Return Value:

The uppercase equivalent of c.

-or-

The unchanged value of c, if c is already uppercase or not alphabetic.

Formatting information is obtained from the current culture.

Use String.ToUpper to convert a string to uppercase.

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Summary

Converts the value of a specified Unicode character to its uppercase equivalent using specified culture-specific formatting information.

C# Syntax:

public static char ToUpper(    char c,    CultureInfo culture );

c

A Unicode character.

culture

A CultureInfo object that supplies culture-specific formatting information, or null.

Return Value:

The uppercase equivalent of c, formatted according to culture.

-or-

The unchanged value of c, if c is already uppercase or not alphabetic.

Exceptions

Exception Type	Condition
ArgumentNullException	culture is null.

Use String.ToUpper to convert a string to uppercase.

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