jQuery-在下拉菜单的确认对话框上取消更改事件 [英] jQuery - cancel change event on confirmation dialog for a Dropdown

问题描述

我有一个下拉菜单，我有jQuery change函数.

I have a dropdown and I have the jQuery change function.

我想根据确认"对话框来实现所选项目的更改.

I would like to implement the change of the selected item as per the Confirmation dialog.

如果确认为是，我可以继续进行选定的更改，否则我将现有项目保留为选定状态并取消更改事件.

If confirms true i can proceed for selected change otherwise I have keep the existing item as selected and cancel the change event.

如何用jQuery实现呢?

How can I implement this with jQuery?

jquery函数

$(function () {
    $("#dropdown").change(function () {
        var success = confirm('Are you sure want to change the Dropdown ????');
        if (success == true) {
            alert('Changed');  
            // do something                  
        }
        else {
            alert('Not changed');
            // Cancel the change event and keep the selected element
        }
    });
});

要记住的一件事change功能仅在更改所选项目后才会命中 因此最好考虑在onchange上实现它-但在jquery中不可用.有什么方法可以实现吗?

One thing to remember change function hits only after selected item changed So better to think to implement this on onchange - but it is not available in jquery. Is there any method to implement this?

推荐答案

好吧，正如Vinu正确指出的那样，只有在select的值实际被更改后，jQuery的change事件才被触发.您最好这样做:

Well, as Vinu has rightly pointed out, jQuery's change event is only triggered once the value of the select has actually been changed. You would be better off doing something like this:

var prev_val;

$('#dropdown').focus(function() {
    prev_val = $(this).val();
}).change(function() {
     $(this).blur() // Firefox fix as suggested by AgDude
    var success = confirm('Are you sure you want to change the Dropdown?');
    if(success)
    {
        alert('changed');
        // Other changed code would be here...
    }  
    else
    {
        $(this).val(prev_val);
        alert('unchanged');
        return false; 
    }
});

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