Force CascadingDropDown to refresh without page reload

How do I force a CascadingDropDown to refresh it's data without a page refresh? I have a button on the page which adds a variable to the Session which is then used to set the selected value of all the drop downs. However I can't seem to force the refresh of a DropDownList without a full refresh of the page.

From stackoverflow weiran

• Let's see - the button on your page probably has an event associated with it to respond to it being clicked, right?

  Can't you just reload and re-assign the data to the dropdown in the button "OnClick" event??

  public void OnButtonClick(.....)
  {
    .....
    CascadingDropDown.DataSource = .......;
    CascadingDropDown.DataBind();
  }
  

  Or am I missing something?

  Cheers, Marc

  From marc_s