title: ExtJS manipulating propertygrid source information
body: <p>I'm using a propertygrid in a similar fashion to a form, rendering a button in the propertygrid tbar to generate an AJAX request, passing the source information to a back-end function that runs a SQL script.</p>
  
  <p>The process of getting the source information to the back-end is proving troublesome, however; while looking at the information in the browser debug console, the result looks like it can be iterated (sample info from console below):</p>
  
  <pre><code>[CNC: "", Cutter_ID: "", Dimension: "", ID: "71",
  Internal_Finish: "Standard White", Item_No: "4", Material_ID: "N/A",
  Production_Item_Type_ID: "Frame(s)", Production_Notes: "", Qty: "1",
  Ready_by_Date: "31 Dec 2014", Survey_Notes: "",
  Thickness_Depth: "95", Type_of_Work_ID: "Complete New"]
  </code></pre>
  
  <p>Selecting individual items can be done, i.e. I can get and set <code>source['Qty']</code>, for instance.</p>
  
  <p>I cannot, however, pass the information in a manageable format; neither can I encode (or decode) the information from the source to JSON.</p>
  
  <p>I would like to at least iterate through the source and append the information to a string, which is then encoded to JSON to pass to the back-end.</p>
  
  <p>How does the propertygrid source work as a data source, since I clearly don't understand it correctly? What method can I employ to generate JSONable information from it?</p>