How to Expire cache
<p>I am using cache to store the data but in some operations such as addition/updation I want to reload the i am using following method but it does not works, is there any other solution</p>

<pre><code>Response.Cache.SetSlidingExpiration(true);
</code></pre>

<p>also tried</p>

<pre><code>cache["MoiveLIst"] = null;
</code></pre>

<p>but no result</p>

<p>Above code should make the if condition true but it does not, and if block does not executes because cache is not null, how i can make it null</p>

<pre><code>if(Cache ["MovieList"]==null)                  
{
     Cache.Insert("MovieList", _client.GetAllMovies(), null, timespane, System.Web.Caching.Cache.NoSlidingExpiration);
}
List&lt;Movie&gt; oData = Cache["MovieList"] as List&lt;Movie&gt;;
</code></pre>
