php - Html button action only on first click

Question

I can set action on click for html button. But I need to set action only on FIRST click. Is there any way to do this? The button is radio in form. Some javascript maybe?

What's important - the radio button still might be changed. But action has to be done only once.

This doesn't work

function myfunction(i){
oForm = document.forms["myform"];
if(oForm.elements["field"+i].checked)
    alert("action done earlier");
else
    action
}

Answer 1

最干净的解决方案可能是使用removeEventListener来...删除事件侦听器：

var myButton = document.getElementById('someId');
var handler = function(){
   // doSomething
   myButton.removeEventListener('click',handler);
}
myButton.addEventListener('click', handler);

（为了使其更干净，您可以将其包装在 IIFE 中，如下例所示）

示范

Answer 2

查看 jQuery .one()事件处理程序。

$("#my-button").one('click', function() {
    /* Do something at most once */
});

Answer 3

为了解决这个问题，我使用了 jQuery.on 和 jQuery.off——在 jsfiddle 上查看我的代码！

$(document).ready(function() {
    var button = $('#my-button');

    function onClick() {
        alert('clicked');
        button.off('click', onClick);
    };

    button.on('click', onClick);
});

http://jsfiddle.net/VxRyn/

Answer 4

如果你更喜欢 jQuery，你可以使用 jQuery unbind

$("button").click(function(){
  /* some content */
  $(this).unbind('click');
});

html

<button> Some content </button>

Answer 5

单击按钮后，您可以使用属性禁用按钮，添加

disabled="disabled"

到按钮一次点击？