为什么在asp.net按钮中调用__doPostback？

Question

I'm trying to figure out why someone would make a call to __doPostback() from an asp.net button. The button seem to postback automatically without having to make that call.

  function getSelected() {
        // set the value of some input field
        __doPostback();
    };


   <asp:Button runat="server" Text="Select Orders" ID="btnSelected"   OnClientClick="javascript:getSelected();">/asp:Button>

Answer 1

Because the function __doPostback sets the event target and event arguments and this is required to correctly process the event on server side. Without calling it, you'll be able to generate a postback but your event handler on server side won't be called.

If you don't have any handler, there is no benefit on calling it.