Char.IsLower Method

Definition

Namespace:

System

Assembly:

System.Runtime.dll

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

Overloads

IsLower(Char)	Indicates whether the specified Unicode character is categorized as a lowercase letter.
IsLower(String, Int32)	Indicates whether the character at the specified position in a specified string is categorized as a lowercase letter.

Examples

The following code example demonstrates IsLower.

using namespace System;
int main()
{
   char ch = 'a';
   Console::WriteLine( Char::IsLower( ch ) ); // Output: "True"
   Console::WriteLine( Char::IsLower(  "upperCase", 5 ) ); // Output: "False"
}

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"
    }
}

open System

let ch = 'a'

printfn $"{Char.IsLower ch}"                    // Output: "True"
printfn $"""{Char.IsLower("upperCase", 5)}"""   // Output: "False"

Module IsLowerSample

    Sub Main()

        Dim ch As Char
        ch = "a"c

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

    End Sub

End Module

IsLower(Char)

Source:

Char.cs

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

public:
 static bool IsLower(char c);

public static bool IsLower (char c);

static member IsLower : char -> bool

Public Shared Function IsLower (c As Char) As Boolean

Parameters

c

Char

The Unicode character to evaluate.

Returns

Boolean

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

Remarks

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

See also

• IsLower(Rune)
• IsUpper(Rune)
• Boolean
• IsUpper(Char)

IsLower(String, Int32)

Source:

Char.cs

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

public:
 static bool IsLower(System::String ^ s, int index);

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

static member IsLower : string * int -> bool

Public Shared Function IsLower (s As String, index As Integer) As Boolean

Parameters

s

String

A string.

index

Int32

The position of the character to evaluate in s.

Returns

Boolean

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

Exceptions

ArgumentNullException

s is null.

ArgumentOutOfRangeException

index is less than zero or greater than the last position in s.

Remarks

Character positions in a string are indexed starting from zero.

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

See also

• Boolean
• String
• IsUpper(Char)