ReadOnly Method

CultureInfo.ReadOnly Method (CultureInfo)


Returns a read-only wrapper around the specified CultureInfo object.

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

public static CultureInfo ReadOnly(
	CultureInfo ci


Type: System.Globalization.CultureInfo

The CultureInfo object to wrap.

Return Value

Type: System.Globalization.CultureInfo

A read-only CultureInfo wrapper around ci.

Exception Condition

ci is null.

This wrapper prevents any modifications to ci, or the objects returned by the ci.DateTimeFormat and ci.NumberFormat properties.

The following example shows that the ReadOnly method helps protect the DateTimeFormatInfo and NumberFormatInfo instances associated with the CultureInfo.

using System;
using System.Globalization;

public class SamplesCultureInfo  {

   public static void Main()  {

      // Creates a CultureInfo.
      CultureInfo myCI = new CultureInfo( "en-US" );

      // Creates a read-only CultureInfo based on myCI.
      CultureInfo myReadOnlyCI = CultureInfo.ReadOnly( myCI );

      // Display the read-only status of each CultureInfo and their DateTimeFormat and NumberFormat properties.
      Console.WriteLine( "myCI is {0}.", myCI.IsReadOnly ? "read only" : "writable" );
      Console.WriteLine( "myCI.DateTimeFormat is {0}.", myCI.DateTimeFormat.IsReadOnly ? "read only" : "writable" );
      Console.WriteLine( "myCI.NumberFormat is {0}.", myCI.NumberFormat.IsReadOnly ? "read only" : "writable" );
      Console.WriteLine( "myReadOnlyCI is {0}.", myReadOnlyCI.IsReadOnly ? "read only" : "writable" );
      Console.WriteLine( "myReadOnlyCI.DateTimeFormat is {0}.", myReadOnlyCI.DateTimeFormat.IsReadOnly ? "read only" : "writable" );
      Console.WriteLine( "myReadOnlyCI.NumberFormat is {0}.", myReadOnlyCI.NumberFormat.IsReadOnly ? "read only" : "writable" );



This code produces the following output.

myCI is writable.
myCI.DateTimeFormat is writable.
myCI.NumberFormat is writable.
myReadOnlyCI is read only.
myReadOnlyCI.DateTimeFormat is read only.
myReadOnlyCI.NumberFormat is read only.


Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top
© 2015 Microsoft