OrderedDictionary.Add Method (Object, Object)


Adds an entry with the specified key and value into the OrderedDictionary collection with the lowest available index.

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

public void Add(
	object key,
	object value


Type: System.Object

The key of the entry to add.

Type: System.Object

The value of the entry to add. This value can be null.

Exception Condition

The OrderedDictionary collection is read-only.

A key cannot be null, but a value can be.

You can also use the Item property to add new elements by setting the value of a key that does not exist in the OrderedDictionary collection; however, if the specified key already exists in the OrderedDictionary, setting the Item property overwrites the old value. In contrast, the Add method does not modify existing elements.

The following code example demonstrates the creation and population of an OrderedDictionary collection. This code is part of a larger code example that can be viewed at OrderedDictionary.

// Creates and initializes a OrderedDictionary.
OrderedDictionary myOrderedDictionary = new OrderedDictionary();
myOrderedDictionary.Add("testKey1", "testValue1");
myOrderedDictionary.Add("testKey2", "testValue2");
myOrderedDictionary.Add("keyToDelete", "valueToDelete");
myOrderedDictionary.Add("testKey3", "testValue3");

ICollection keyCollection = myOrderedDictionary.Keys;
ICollection valueCollection = myOrderedDictionary.Values;

// Display the contents using the key and value collections
DisplayContents(keyCollection, valueCollection, myOrderedDictionary.Count);

Universal Windows Platform
Available since 10
.NET Framework
Available since 2.0
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