IDictionary.Remove(Object) Method

Definition

Namespace:

System.Collections

Assembly:

System.Runtime.dll

Removes the element with the specified key from the IDictionary object.

public:
 void Remove(System::Object ^ key);

public void Remove (object key);

abstract member Remove : obj -> unit

Public Sub Remove (key As Object)

Parameters

key

Object

The key of the element to remove.

Exceptions

ArgumentNullException

key is null.

NotSupportedException

The IDictionary object is read-only.

-or-

The IDictionary has a fixed size.

Examples

The following code example demonstrates how to implement the Remove method. This code example is part of a larger example provided for the IDictionary class.

public:
    virtual void Remove(Object^ key)
    {
        if (key == nullptr)
        {
            throw gcnew ArgumentNullException("key");
        }
        // Try to find the key in the DictionaryEntry array
        int index;
        if (TryGetIndexOfKey(key, &index))
        {
            // If the key is found, slide all the items down.
            Array::Copy(items, index + 1, items, index, itemsInUse -
                index - 1);
            itemsInUse--;
        }
        else
        {
            // If the key is not in the dictionary, just return.
            return;
        }
    }

public void Remove(object key)
{
    if (key == null) throw new ArgumentNullException("key");
    // Try to find the key in the DictionaryEntry array
    Int32 index;
    if (TryGetIndexOfKey(key, out index))
    {
        // If the key is found, slide all the items up.
        Array.Copy(items, index + 1, items, index, ItemsInUse - index - 1);
        ItemsInUse--;
    }
    else
    {
        // If the key is not in the dictionary, just return.
    }
}

Public Sub Remove(ByVal key As Object) Implements IDictionary.Remove
    If key = Nothing Then
        Throw New ArgumentNullException("key")
    End If
    ' Try to find the key in the DictionaryEntry array
    Dim index As Integer
    If TryGetIndexOfKey(key, index) Then

        ' If the key is found, slide all the items up.
        Array.Copy(items, index + 1, items, index, (ItemsInUse - index) - 1)
        ItemsInUse = ItemsInUse - 1
    Else

        ' If the key is not in the dictionary, just return. 
    End If
End Sub

Remarks

If the IDictionary object does not contain an element with the specified key, the IDictionary remains unchanged. No exception is thrown.