Error when reading data in to ArrayCollection using HTTPService

Question

Hi,
I am trying to read data in to ArrayCollection using HTTPService result property:
[Bindable] private var myData:ArrayCollection=new ArrayCollection();
   private function result_handler(e:ResultEvent):void
        myData = e.result.root.contact;
  <mx:HTTPService id="post_submit"
       url="test.php"
       method="POST"
       result="result_handler(event)"
       fault="fault_handler(event)">
       <mx:request xmlns="">
       </mx:request>
   </mx:HTTPService>
I am getting the following error when there is no "contact" record in the xml root:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
Also I am getting the following error when there is only ONE  "contact" record in the xml root:
TypeError: Error #1034: Type Coercion failed: cannot convert mx.utils::ObjectProxy@280c9ca1 to mx.collections.ArrayCollection.
And it works fine when there is two or more "contact" records in the xml root.
Am I missing something?
Thanks

Answer 1

I am getting the following error when there is no "contact" record in the xml root:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
     You'll be getting this error because it's trying to access nodes that don't exist;
     there are no 'contact' records, thus when it tries to access node 'root.contact', it doesn't exist, hence it's receiving NULL when it's expecting      something
Also I am getting the following error when there is only ONE  "contact" record in the xml root:TypeError: Error #1034: Type Coercion failed: cannot convert mx.utils::ObjectProxy@280c9ca1 to mx.collections.ArrayCollection.
And it works fine when there is two or more "contact" records in the xml root.
Am I missing something?
Thanks
      When there is only 1 value, it'll be returned as an object (Arrays are used for multiple items). So it throws an error as it isn't expecting a single           object, it wants an Array.
     This is also why when it returns 2+ records, there is no error. Multiple results will be returned as an Array, what your flex app was expecting.
     My initial guess to solve the first problem would be similar to Greg's, although i'm guessing you'd want;
    if(e.result != null){
     instead of
     if(e.result.root.contact != null){
    as you'd initially want to check if anything was returned in the result, rather than checking to see if a certain node exists.
     If you attempt to see if a certain node isn't null, and the node doesn't exist, it'll probably throw another #1009
     For the #1034 error, you'll have to check to see how many results were returned, as Madhav has described for you.