how to know whether modal boxes (alert, prompt, confirm…) have been disabled in javascript?

问题

I have a private web based app where sometimes I genuinely ask to the users what they want to do in given situations. To do so, I'm using the confirm function of javascript.

As any other modal box, after a few popups the user has the choice to disable them by simply clicking the little box as showed below:

The problem is that, if they clicked it once, they never see other messages and responses to confirm are assumed 0, which is confusing because basically it means that all the actions requiring their confirmation are cancelled with no warning! Refreshing the page does not help, they have to close it and reopen it for it to work again.

Can I detect when they checked that little box?

回答1:

When that box is checked, the dialog "closes" immediately. You could check to see if the box closes unusually fast:

function dialog(message, success, failure) {
    var open_time = new Date();
    var result = alert(message);
    var close_time = new Date();

    if (close_time - open_time < 10) {
        failure();
    } else {
        success(result);
    }
}

dialog('Hello', function(result) {
    // The dialog probably was closed by the user
}, function() {
    // The dialog was closed really fast.
    // Either the user was typing while it popped up or the browser didn't
    //  display it in the first place
});

Although just using CSS and HTML to create modal dialogs would probably be much easier and more consistent across browsers and platforms. I personally don't like Chrome's approach.

Demo: http://jsfiddle.net/tS9G6/4/

I looked a little bit through Chromium's source and that property isn't stored anywhere, so there doesn't seem to be some Chromium-specific property that you can look at.

回答2:

You can't do anything about it. It's a browser feature.

You can check for the timing -

How to Detect "prevent this page from creating additional dialogs"

This suggests doing the following :

function myConfirm(message){
    var start = new Date().getTime();
    var result = confirm(message);
    var dt = new Date().getTime() - start;
    // dt < 50ms means probable computer
    // the quickest I could get while expecting the popup was 100ms
    // slowest I got from computer suppression was 20ms
    for(var i=0; i < 10 && !result && dt < 50; i++){
        start = new Date().getTime();
        result = confirm(message);
        dt = new Date().getTime() - start;
    }
    if(dt < 50)
       return true;
    return result;
}

来源：https://stackoverflow.com/questions/20672490/how-to-know-whether-modal-boxes-alert-prompt-confirm-have-been-disabled-i

标签

javascript

modal-dialog