Extension methods for IEnumerable interfaces

<summary>
The extension method of the IEnumerable interface, the implementation class that supports it is the case of list
</summary>
Using System.Collections.Generic;
public static Class Ienumerableextensions
{
<summary>
Adding elements to the collection
</summary>
<typeparam name= "T" ></typeparam>
<param name= "Collection" ></param>
<param name= "Value" ></param>
public static void Add<t> (this ienumerable<t> collection, T value)
{
(collection as list<t>). ADD (value);
}
<summary>
Remove an element from the collection
</summary>
<typeparam name= "T" ></typeparam>
<param name= "Collection" ></param>
<param name= "Value" ></param>
public static void Remove<t> (this ienumerable<t> collection, T value)
{
(collection as list<t>). Remove (value);
}
<summary>
Retrieves whether an element is contained in the collection
</summary>
<typeparam name= "T" ></typeparam>
<param name= "Collection" ></param>
<param name= "Value" ></param>
<returns></returns>
public static bool Contains<t> (this ienumerable<t> collection, T value)
{
Return (collection as list<t>). Contains (value);
}
}

Extension methods for IEnumerable interfaces