Hashtable.Clear Method ()

 

Removes all elements from the Hashtable.

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

public virtual void Clear()

Exception Condition
NotSupportedException

The Hashtable is read-only.

Count is set to zero, and references to other objects from elements of the collection are also released. The capacity remains unchanged.

This method is an O(n) operation, where n is Count.

The following example shows how to clear the values of the Hashtable.

using System;
using System.Collections;
public class SamplesHashtable  {

   public static void Main()  {

      // Creates and initializes a new Hashtable.
      Hashtable myHT = new Hashtable();
      myHT.Add( "one", "The" );
      myHT.Add( "two", "quick" );
      myHT.Add( "three", "brown" );
      myHT.Add( "four", "fox" );
      myHT.Add( "five", "jumped" );

      // Displays the count and values of the Hashtable.
      Console.WriteLine( "Initially," );
      Console.WriteLine( "   Count    : {0}", myHT.Count );
      Console.WriteLine( "   Values:" );
      PrintKeysAndValues( myHT );

      // Clears the Hashtable.
      myHT.Clear();

      // Displays the count and values of the Hashtable.
      Console.WriteLine( "After Clear," );
      Console.WriteLine( "   Count    : {0}", myHT.Count );
      Console.WriteLine( "   Values:" );
      PrintKeysAndValues( myHT );
   }


   public static void PrintKeysAndValues( Hashtable myHT )  {
      Console.WriteLine( "\t-KEY-\t-VALUE-" );
      foreach ( DictionaryEntry de in myHT )
         Console.WriteLine( "\t{0}:\t{1}", de.Key, de.Value );
      Console.WriteLine();
   }

}


/* 
This code produces the following output.

Initially,
   Count    : 5
   Values:
        -KEY-   -VALUE-
        two:    quick
        three:  brown
        four:   fox
        five:   jumped
        one:    The

After Clear,
   Count    : 0
   Values:
        -KEY-   -VALUE-

*/ 

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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