TextInfo.ToLower Method (String)

Converts the specified string to lowercase.

Namespace:  System.Globalization
Assemblies:   System.Globalization (in System.Globalization.dll)
  mscorlib (in mscorlib.dll)

public virtual string ToLower(
	string str
)

Parameters

str
Type: System.String

The string to convert to lowercase.

Return Value

Type: System.String
The specified string converted to lowercase.

ExceptionCondition
ArgumentNullException

str is null.

The returned string might differ in length from the input string. For more information on casing, refer to the Unicode Technical Report #21 "Case Mappings," published by the Unicode Consortium (http://www.unicode.org). The current implementation preserves the length of the string. However, this behavior is not guaranteed and could change in future implementations.

Casing semantics depend on the culture in use. For the invariant culture, the casing semantics are not culture-sensitive. For a specific culture, the casing semantics are sensitive to that culture.

If a security decision depends on a string comparison or a case-change operation, the application should use the InvariantCulture to ensure that the behavior is consistent regardless of the culture settings of the system. However, the invariant culture must be used only by processes that require culture-independent results, such as system services. Otherwise, it produces results that might be linguistically incorrect or culturally inappropriate.

For more information on cultures, see CultureInfo.

The following code example changes the casing of a string based on the English (United States) culture, with the culture name en-US.

using System;
using System.Globalization;


public class SamplesTextInfo  {

   public static void Main()  {

      // Defines the string with mixed casing. 
      string myString = "wAr aNd pEaCe";

      // Creates a TextInfo based on the "en-US" culture.
      TextInfo myTI = new CultureInfo("en-US",false).TextInfo;

      // Changes a string to lowercase.
      Console.WriteLine( "\"{0}\" to lowercase: {1}", myString, myTI.ToLower( myString ) );

      // Changes a string to uppercase.
      Console.WriteLine( "\"{0}\" to uppercase: {1}", myString, myTI.ToUpper( myString ) );

      // Changes a string to titlecase.
      Console.WriteLine( "\"{0}\" to titlecase: {1}", myString, myTI.ToTitleCase( myString ) );

   }

}

/*
This code produces the following output.

"wAr aNd pEaCe" to lowercase: war and peace
"wAr aNd pEaCe" to uppercase: WAR AND PEACE
"wAr aNd pEaCe" to titlecase: War And Peace

*/

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback
Show:
© 2015 Microsoft