Question

Following this problem ASP.NET: OnServerClick event handler not called if using onclick

I implemented a workaround:

<button id="idBtnPrint" runat="server" type="submit" onserverclick="BtnPrint_Click" onclick="confirmImpression();">print</button>

javascript function:

    function confirmImpression() {

        if (!confirm("sure ?"))
            arg.whatever;

    }

where confirmation is positive the postback is started when cancel the postback is not run (as I want) simply because an error generated js “arg is undefined” (normal because arg is not instanciate) script is locked and therefore no postback (as I want too).

but how to do this properly. I would not see the error appear in the status bar in the browser.

any suggestion is welcome!

thank you

Answer 1

Simply wrap the confirmation in an if-block and return false if the confirmation fails. The standard javascript that generates the postback will be appended to the check and thus be run if the action is confirmed.

<button id="idBtnPrint" runat="server" type="submit"
        onserverclick="BtnPrint_Click"
        onclientclick="if (!confirm('sure ?')) { return false; }">print</button>

The reason that arg is undefined is that you don’t use it as an argument nor is it defined in the window object. I assume that you’re trying to hook into the validation system, but it won’t work in this case because the validation logic isn’t being invoked. You simply want to stop execution of the client-side handler if the user answers in the negative and the above code will do that.

Though the answer in the referenced question will work as well I prefer to use a full javascript statement to aid in understanding what is going on.