StringToUpper Method
 

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

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

public string ToUpper(
	CultureInfo culture
)
public:
String^ ToUpper(
	CultureInfo^ culture
)
member ToUpper : 
        culture:CultureInfo -> string
Public Function ToUpper (
	culture As CultureInfo
) As String

Parameters

culture
Type:

An object that supplies culture-specific casing rules.

Return Value

Type:

The uppercase equivalent of the current string.

Exception Condition
ArgumentNullException

culture is null.

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

System_CAPS_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 converted to uppercase.

If you pass the ToUpper method a CultureInfo object other than , the casing operation will take culture-specific rules into account. If you need the lowercase or uppercase version of an operating system identifier, such as a file name, named pipe, or registry key, use the ToLowerInvariant or ToUpperInvariant method. This produces the same result in every culture and performs more efficiently.

The following example converts a string of lowercase characters to two strings of uppercase characters using the English-United States and Turkish-Turkey cultures, then compares the uppercase 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.

using System;
using System.Globalization;

class Example 
{
    public static void Main() 
    {
       string str1 = "indigo";
       string str2, str3;

       // str2 is an uppercase copy of str1, using English-United States culture.
       str2 = str1.ToUpper(new CultureInfo("en-US", false));

       // str3 is an uppercase copy of str1, using Turkish-Turkey culture.
       str3 = str1.ToUpper(new CultureInfo("tr-TR", false));

       // Compare the code points and compare the uppercase strings.
       ShowCodePoints("str1", str1);
       ShowCodePoints("str2", str2);
       ShowCodePoints("str3", str3);
       Console.WriteLine("str2 is {0} to str3.", 
            String.CompareOrdinal(str2, str3) == 0 ? "equal" : "not equal");
    }

    public static void ShowCodePoints(string varName, string s)
    {
       Console.Write("{0} = {1}: ", varName, s);
       foreach (ushort u in s)
         Console.Write("{0:x4} ", u);
       Console.WriteLine();
    }
}
// This example displays the following output:
//       str1 = indigo: 0069 006e 0064 0069 0067 006f
//       str2 = INDIGO: 0049 004e 0044 0049 0047 004f
//       str3 = INDIGO: 0130 004e 0044 0130 0047 004f
//       str2 is not equal to str3.
Imports System.Globalization

Public Module Example
   Public Sub Main()
      Dim str1 As String = "indigo"
      Dim str2, str3 As String

      ' str2 is an uppercase copy of str1, using English-United States culture.
      str2 = str1.ToUpper(New CultureInfo("en-US", False))

      ' str3 is an uppercase copy of str1, using Turkish-Turkey culture.
      str3 = str1.ToUpper(New CultureInfo("tr-TR", False))

      ' Compare the code points and compare the uppercase strings.
      ShowCodePoints("str1", str1)
      ShowCodePoints("str2", str2)
      ShowCodePoints("str3", str3)
      Console.WriteLine("str2 is {0} to str3.", _
                        IIf(String.CompareOrdinal(str2, str3) = 0, "equal", "not equal"))
   End Sub

   Public Sub ShowCodePoints(varName As String, s As String)
      Console.Write("{0} = {1}: ", varName, s)
      For Each c In s
         Console.Write("{0:X4} ", AscW(c))
      Next
      Console.WriteLine() 
   End Sub 
End Module
' The example displays the following output:
'       str1 = indigo: 0069 006E 0064 0069 0067 006F
'       str2 = INDIGO: 0049 004E 0044 0049 0047 004F
'       str3 = İNDİGO: 0130 004E 0044 0130 0047 004F
'       str2 is not equal to str3.
.NET Framework
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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