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ResourceSet.GetEnumerator Method

Definition

Returns an IDictionaryEnumerator that can iterate through the ResourceSet.

public:
 virtual System::Collections::IDictionaryEnumerator ^ GetEnumerator();
public virtual System.Collections.IDictionaryEnumerator GetEnumerator ();
[System.Runtime.InteropServices.ComVisible(false)]
public virtual System.Collections.IDictionaryEnumerator GetEnumerator ();
abstract member GetEnumerator : unit -> System.Collections.IDictionaryEnumerator
override this.GetEnumerator : unit -> System.Collections.IDictionaryEnumerator
[<System.Runtime.InteropServices.ComVisible(false)>]
abstract member GetEnumerator : unit -> System.Collections.IDictionaryEnumerator
override this.GetEnumerator : unit -> System.Collections.IDictionaryEnumerator
Public Overridable Function GetEnumerator () As IDictionaryEnumerator

Returns

An IDictionaryEnumerator for this ResourceSet.

Attributes

Exceptions

The resource set has been closed or disposed.

Examples

The following example demonstrates how to create a ResourceSet rs for the file items.resources. Next, the GetEnumerator method is used to create an IDictionaryEnumerator for rs. The IDictionaryEnumerator iterates through rs and displays the contents to the console.

using namespace System;
using namespace System::Resources;
using namespace System::Collections;
int main()
{
   
   // Create a ResourceSet for the file items.resources.
   ResourceSet^ rs = gcnew ResourceSet( "items.resources" );
   
   // Create an IDictionaryEnumerator* to read the data in the ResourceSet.
   IDictionaryEnumerator^ id = rs->GetEnumerator();
   
   // Iterate through the ResourceSet and display the contents to the console.
   while ( id->MoveNext() )
      Console::WriteLine( "\n [{0}] \t {1}", id->Key, id->Value );

   rs->Close();
}
using System;
using System.Resources;
using System.Collections;

class EnumerateResources 
{
    public static void Main() 
    {
        // Create a ResourceSet for the file items.resources.
        ResourceSet rs = new ResourceSet("items.resources"); 

        // Create an IDictionaryEnumerator to read the data in the ResourceSet.
        IDictionaryEnumerator id = rs.GetEnumerator(); 

        // Iterate through the ResourceSet and display the contents to the console. 
        while(id.MoveNext())
          Console.WriteLine("\n[{0}] \t{1}", id.Key, id.Value); 

        rs.Close();
    }
}
Imports System.Resources
Imports System.Collections

Class EnumerateResources
   
   Public Shared Sub Main()
      ' Create a ResourceSet for the file items.resources.
      Dim rs As New ResourceSet("items.resources")      
      
      ' Create an IDictionaryEnumerator to read the data in the ResourceSet.
      Dim id As IDictionaryEnumerator = rs.GetEnumerator()
      
      ' Iterate through the ResourceSet and display the contents to the console. 
      While id.MoveNext()
         Console.WriteLine(ControlChars.NewLine + "[{0}] " + ControlChars.Tab + "{1}", id.Key, id.Value)
      End While 

      rs.Close()

   End Sub

End Class

Remarks

Enumerators only allow reading the data in the collection. Enumerators cannot be used to modify the underlying collection.

Initially, the enumerator is positioned before the first element in the collection. Reset also brings the enumerator back to this position. At this position, calling Current throws an exception. Therefore, you must call MoveNext to advance the enumerator to the first element of the collection before reading the value of Current.

Current returns the same object until either MoveNext or Reset is called. MoveNext sets Current to the next element.

After the end of the collection is passed, the enumerator is positioned after the last element in the collection, and calling MoveNext returns false. If the last call to MoveNext returned false, calling Current throws an exception. To set Current to the first element of the collection again, you can call Reset followed by MoveNext.

An enumerator remains valid as long as the collection remains unchanged. If changes are made to the collection, such as adding, modifying or deleting elements, the enumerator is irrecoverably invalidated and the next call to MoveNext or Reset throws an InvalidOperationException. If the collection is modified between MoveNext and Current, Current will return the element that it is set to, even if the enumerator is already invalidated.

You can use the IDictionaryEnumerator.Entry property to access the value stored in the current element. Use the IDictionaryEnumerator.Key property to access the key of the current element. Use the IDictionaryEnumerator.Value property to access the value of the current element.

The enumerator does not have exclusive access to the collection; therefore, enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads could still modify the collection, which causes the enumerator to throw an exception. To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.

Applies to