title: Changing a user created control based on content of input from JS tied textbox
body: <p>I want to change a user created control based on content of the input inside of textbox tied to JS.</p>
  
  <p>My user control has an attribute field titled "userInput" where I pass the content of the textbox.</p>
  
  <p>My page looks like this:<img src="https://imgur.com/8wk5b.png" alt="alt text"></p>
  
  <p>The textbox has an autocompleteextender and a Javascript function runs when an item from the dropdown is selected. </p>
  
  <p>How do I pass the selected value back to the server so that my ascx user control can be updated with the appropriate data. (corresponding to what is in the textbox)</p>
  
  <p>Assume that updatepanels/scriptmanagers are set up correctly (they are :-) )</p>