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String.ToLower Method (CultureInfo)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Returns a copy of this string converted to lowercase, using the casing rules of the specified culture.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Function ToLower ( _
    culture As CultureInfo _
) As String

public string ToLower(
    CultureInfo culture
)

Parameters

Return Value

Type: System.String
The lowercase equivalent of the current string.

Exceptions

Exception Condition
ArgumentNullException

culture is nulla null reference (Nothing in Visual Basic).

Remarks

The casing rules of the culture specified by the culture parameter determine the way the case of the string is changed.

NoteNote:

This method does not modify the value of the current instance. Instead, it returns a new string in which all characters in the current instance are lowercased.

Examples

The following code example converts two strings of uppercase characters to lowercase characters using the English-United States and Turkish-Turkey cultures, then compares the lowercase strings. The uppercase strings are identical except that for each occurrence of the Unicode LATIN CAPITAL LETTER I in one string, the other string contains LATIN CAPITAL LETTER I WITH DOT ABOVE.

' Sample for String.ToLower(CultureInfo)
Imports System.Globalization

Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim str1 As [String] = "INDIGO"
      ' str2 = str1, except each 'I' is '\u0130' (Unicode LATIN CAPITAL I WITH DOT ABOVE).
      Dim str2 As New [String](New [Char]() {ChrW(&H130), "N"c, "D"c, ChrW(&H130), "G"c, "O"c})
      Dim str3, str4 As [String]

      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format("str1 = '{0}'", str1) & vbCrLf

      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format("str1 is {0} to str2.", _
                         IIf(0 = [String].CompareOrdinal(str1, str2), "equal", "not equal")) & vbCrLf
      CodePoints(outputBlock, "str1", str1)
      CodePoints(outputBlock, "str2", str2)

      outputBlock.Text &= vbCrLf
      ' str3 is a lower case copy of str2, using English-United States culture.
      outputBlock.Text &= "str3 = Lower case copy of str2 using English-United States culture." & vbCrLf
      str3 = str2.ToLower(New CultureInfo("en-US"))

      ' str4 is a lower case copy of str2, using Turkish-Turkey culture.
      outputBlock.Text &= "str4 = Lower case copy of str2 using Turkish-Turkey culture." & vbCrLf
      str4 = str2.ToLower(New CultureInfo("tr-TR"))

      ' Compare the code points in str3 and str4.
      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format("str3 is {0} to str4.", _
                         IIf(0 = [String].CompareOrdinal(str3, str4), "equal", "not equal")) & vbCrLf
      CodePoints(outputBlock, "str3", str3)
      CodePoints(outputBlock, "str4", str4)
   End Sub 'Main

   Public Shared Sub CodePoints(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal title As [String], ByVal s As [String])
      outputBlock.Text &= String.Format("{0}The code points in {1} are: {0}", vbCrLf, title)
      Dim c As Char
      For Each c In s
         outputBlock.Text &= String.Format("{0:x4} ", AscW(c))
      Next c
      outputBlock.Text &= vbCrLf
   End Sub 'CodePoints
End Class 'Sample
'
'str1 = 'INDIGO'
'
'str1 is not equal to str2.
'
'The code points in str1 are:
'0049 004e 0044 0049 0047 004f
'
'The code points in str2 are:
'0130 004e 0044 0130 0047 004f
'
'str3 = Lower case copy of str2 using English-United States culture.
'str4 = Lower case copy of str2 using Turkish-Turkey culture.
'
'str3 is equal to str4.
'
'The code points in str3 are:
'0069 006e 0064 0069 0067 006f
'
'The code points in str4 are:
'0069 006e 0064 0069 0067 006f

// Sample for String.ToLower(CultureInfo)

using System;
using System.Globalization;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      String str1 = "INDIGO";
      // str2 = str1, except each 'I' is '\u0130' (Unicode LATIN CAPITAL I WITH DOT ABOVE).
      String str2 = new String(new Char[] { '\u0130', 'N', 'D', '\u0130', 'G', 'O' });
      String str3, str4;

      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("str1 = '{0}'", str1) + "\n";

      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("str1 is {0} to str2.",
           ((0 == String.CompareOrdinal(str1, str2)) ? "equal" : "not equal")) + "\n";
      CodePoints(outputBlock, "str1", str1);
      CodePoints(outputBlock, "str2", str2);

      outputBlock.Text += "\n";
      // str3 is a lower case copy of str2, using English-United States culture.
      outputBlock.Text += "str3 = Lower case copy of str2 using English-United States culture." + "\n";
      str3 = str2.ToLower(new CultureInfo("en-US"));

      // str4 is a lower case copy of str2, using Turkish-Turkey culture.
      outputBlock.Text += "str4 = Lower case copy of str2 using Turkish-Turkey culture." + "\n";
      str4 = str2.ToLower(new CultureInfo("tr-TR"));

      // Compare the code points in str3 and str4.
      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("str3 is {0} to str4.",
           ((0 == String.CompareOrdinal(str3, str4)) ? "equal" : "not equal")) + "\n";
      CodePoints(outputBlock, "str3", str3);
      CodePoints(outputBlock, "str4", str4);
   }

   public static void CodePoints(System.Windows.Controls.TextBlock outputBlock, String title, String s)
   {
      outputBlock.Text += String.Format("{0}The code points in {1} are: {0}", "\n", title);
      foreach (ushort u in s)
         outputBlock.Text += String.Format("{0:x4} ", u);
      outputBlock.Text += "\n";
   }
}
/*
This example produces the following results:

str1 = 'INDIGO'

str1 is not equal to str2.

The code points in str1 are:
0049 004e 0044 0049 0047 004f

The code points in str2 are:
0130 004e 0044 0130 0047 004f

str3 = Lower case copy of str2 using English-United States culture.
str4 = Lower case copy of str2 using Turkish-Turkey culture.

str3 is equal to str4.

The code points in str3 are:
0069 006e 0064 0069 0067 006f

The code points in str4 are:
0069 006e 0064 0069 0067 006f
*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.