TextInfo.ToUpper Method

Definition

Converts the specified character or string to uppercase.

Overloads

ToUpper(Char)

Converts the specified character to uppercase.

ToUpper(String)

Converts the specified string to uppercase.

ToUpper(Char)

Converts the specified character to uppercase.

public:
 virtual char ToUpper(char c);
public virtual char ToUpper (char c);
abstract member ToUpper : char -> char
override this.ToUpper : char -> char
Public Overridable Function ToUpper (c As Char) As Char

Parameters

c
Char

The character to convert to uppercase.

Returns

The specified character converted to uppercase.

Examples

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

using namespace System;
using namespace System::Globalization;
int main()
{
   
   // Defines the String* with mixed casing.
   String^ myString = "wAr aNd pEaCe";
   
   // Creates a TextInfo based on the S"en-US" culture.
   CultureInfo^ MyCI = gcnew CultureInfo( "en-US",false );
   TextInfo^ myTI = MyCI->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.

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

*/
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

*/
Imports System.Globalization

Public Class SamplesTextInfo

   Public Shared Sub Main()

      ' Defines the string with mixed casing.
      Dim myString As String = "wAr aNd pEaCe"

      ' Creates a TextInfo based on the "en-US" culture.
      Dim myTI As TextInfo = 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))

   End Sub

End Class


'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


Remarks

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.

See also

ToUpper(String)

Converts the specified string to uppercase.

public:
 virtual System::String ^ ToUpper(System::String ^ str);
public virtual string ToUpper (string str);
abstract member ToUpper : string -> string
override this.ToUpper : string -> string
Public Overridable Function ToUpper (str As String) As String

Parameters

str
String

The string to convert to uppercase.

Returns

The specified string converted to uppercase.

Exceptions

str is null.

Examples

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

using namespace System;
using namespace System::Globalization;
int main()
{
   
   // Defines the String* with mixed casing.
   String^ myString = "wAr aNd pEaCe";
   
   // Creates a TextInfo based on the S"en-US" culture.
   CultureInfo^ MyCI = gcnew CultureInfo( "en-US",false );
   TextInfo^ myTI = MyCI->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.

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

*/
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

*/
Imports System.Globalization

Public Class SamplesTextInfo

   Public Shared Sub Main()

      ' Defines the string with mixed casing.
      Dim myString As String = "wAr aNd pEaCe"

      ' Creates a TextInfo based on the "en-US" culture.
      Dim myTI As TextInfo = 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))

   End Sub

End Class


'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


Remarks

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 (https://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.

See also

Applies to