title: How do I combine the contents of two lists?
body: <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>