Jquery trap form submit()

问题:

I'm currently using jquery to trap the submission of a form and show users a dialog for confirmation. If user clicks yes, then form should submit. If user clicks no, then close the dialog.

This all works well but for one issue: when the user clicks yes, this then triggers the same code again, and the dialog is re-opened.

$("#myform").submit(function (event) {
    if (something) {
        var $dialog = $('<div></div>').dialog({
            buttons: {
                "OK": function () {
                    $dialog.dialog('close');
                    $("#myform").submit();
                    return;
                },
                Cancel: function () {
                    $(this).dialog("close");
                }
            }
        });
        $dialog.dialog('open');
        event.preventDefault();
        return false;
    } else {
        $("#myform").submit();
    }
});

I understand why this is happening, just not sure on the best way to get around it. I realise that I could show the modal on button click, instead of form submit, but this doesnt get around the problem of user hitting enter button on keyboard to submit the form.

回答1:

Because when you submit the form, the submit event triggers again and so the event handler. You need to unbind the submit event handler when user says OK. Try this

$("#myform").submit(function (event) {
    if (something) {
        var $dialog = $('<div></div>').dialog({
            buttons: {
                "OK": function () {
                    $dialog.dialog('close');
                    //Check this line - unbinding the submit event handler
                    $("#myform").unbind('submit').submit();
                    return;
                },
                Cancel: function () {
                    $(this).dialog("close");
                }
            }
        });
        $dialog.dialog('open');
        event.preventDefault();
        return false;
    } else {
        $("#myform").submit();
    }
});

回答2:

You should return false when OK:

$("#myform").submit(function (event) {
    if (something) {
        var $dialog = $('<div></div>').dialog({
            buttons: {
                "OK": function () {
                    $dialog.dialog('close');
                    $("#myform").submit();
                    return false; // <=== not just return;
                },
                Cancel: function () {
                    $(this).dialog("close");
                }
            }
        });
        $dialog.dialog('open');
        event.preventDefault();
        return false;
    } else {
        $("#myform").submit();
    }
});

Or delete the manual submit:

buttons: {
"OK": function () {
    $dialog.dialog('close');
    //$("#myform").submit();  <-- delete it
    return;
},

回答3:

Intstead of using the jQuery object to submit the form, you can use the DOM element that the jQuery object refers to to submit the form. This bypasses the jQuery event handler. Your OK function would look like this:

"OK": function () {
    $dialog.dialog('close');
    $("#myform").get(0).submit(); // use the underlying DOM element to sumbit
    return false;
},

回答4:

I would make something either a namespaced global, or a value from some hidden input like so:

var something = nameSpaced.something ||  $('#hiddenInput').val(); //your choice
if (something) {
    ...
} ...

Your logic should work normally then.