title: validation for custom list sharepoint
body: <p>I have created a custom list as a feature in sharepoint.</p>
  
  <p>i need to perform some validation on some of the fields.
  ive created a clss that inherits from SPItemEventReceiver</p>
  
  <p>and need to implement the method:</p>
  
  <pre><code>public override void ItemAdding(SPItemEventProperties properties)
  </code></pre>
  
  <p>where do i take it from here? how do i access list items etc...</p>
  
  <p>thanks</p>