How do prevent multiple submits in a web part

Question

I have a visual web part that has an update panel that has a button that performs an action. I want to prevent users from hitting that button more than once.

The solutions I found use javascript to disable the button then do the postback.

The problem with this that I am having is that my buttonclick method is getting called 2 times since it seems to go to Page_Load 2 times.

Here is my code. First the button and javascript then the Page_Load method.

 <script type="text/javascript">
    function DisableButton() {
        document.getElementById('<%= BetOnCar.ClientID %>').disabled = "disabled";
        __doPostBack('<%= BetOnCar.ClientID %>', ''); 

    } 
</script> 

<asp:Button ID="BetOnCar" runat="server" Text="Bet" OnClientClick="DisableButton();" onclick="BetOnCar_Click" Enabled="false" />

protected void Page_Load(object sender, EventArgs e)
    {
        string controlName = this.Page.Request["__EVENTTARGET"];
        if (BetOnCar.ClientID == this.Page.Request["__EVENTTARGET"])
        {
            BetOnCar_Click(sender, e);
        }
    }

I'm hoping that I am doing this type of thing in the wrong location because it seems like page_load gets hit more often than I expected.

Answer 1

I think you have add return false; in the javascript function DisableButton() OR use Jquery event.preventDefault() .

As the default button click is also firing

Answer 2

You'll get two post backs since you're adding a __doPostBack() in your DisableButton() function. Try to remove that one.