How do I combine the contents of two lists?
<p>I have two <code>List&lt;int&gt;</code> instances.  Now I want to combine them into a third list.</p>

<pre><code>public List&lt;int&gt; oldItemarry1 // storing old item
{
    get 
    { 
        return (List&lt;int&gt;)ViewState["oldItemarry1 "]; 
    }
    set 
    { 
        ViewState["oldItemarry1 "] = value; 
    }
}

public List&lt;int&gt; newItemarry1 // storing new item
{
    get
    { 
        return (List&lt;int&gt;)ViewState["newItemarry1 "]; 
    }
    set 
    { 
        ViewState["newItemarry1 "] = value; 
    }
}

public List&lt;int&gt; Itemarry1 // want to combine both the item
{
    get
    { 
        return (List&lt;int&gt;)ViewState["Itemarry1 "]; 
    }
    set 
    { 
        ViewState["Itemarry1 "] = value; 
    }
}
</code></pre>

<p>Please some one tell me how to do that?</p>
