javascript - 如何手动触发onchange事件？ [重复](How can I trigger an onchange event manually? [duplicate])

Question

This question already has an answer here:(这个问题已经在这里有了答案：)

How to trigger event in JavaScript?(如何在JavaScript中触发事件？) 17 answers(17个答案)

I'm setting a date-time textfield value via a calendar widget.(我正在通过日历窗口小部件设置日期时间文本字段值。)

Obviously, the calendar widget does something like this :(显然，日历小部件会执行以下操作：) document.getElementById('datetimetext').value = date_value; What I want is : On changing value in the date-time textfield I need to reset some other fields in the page.(我想要的是：在更改日期时间文本字段中的值时，我需要重置页面中的其他一些字段。) I've added a onchange event listener to the datetimetext field which is not getting triggered, because I guess onchange gets triggered only when the element gets focus & its value is changed on losing focus.(我已经将一个onchange事件侦听器添加到了不会被触发的datetimetext字段中，因为我猜onchange仅在元素获得焦点并且其值更改为失去焦点时才被触发。) Hence I'm looking for a way to manually trigger this onchange event (which I guess should take care of checking the value difference in the text field).(因此，我正在寻找一种手动触发此onchange事件的方法（我认为应该注意检查文本字段中的值差异）。) Any ideas ?(有任何想法吗 ？)   ask by CodeTweetie translate from so

Answer 1

There's a couple of ways you can do this.(有两种方法可以做到这一点。)

If the onchange listener is a function set via the element.onchange property and you're not bothered about the event object or bubbling/propagation, the easiest method is to just call that function:(如果onchange侦听器是通过element.onchange属性设置的函数，并且您不必担心事件对象或冒泡/传播，那么最简单的方法是只调用该函数：) element.onchange(); If you need it to simulate the real event in full, or if you set the event via the html attribute or addEventListener / attachEvent , you need to do a bit of feature detection to correctly fire the event:(如果您需要它来完全模拟真实事件，或者通过html属性或addEventListener / attachEvent设置事件，则需要做一些功能检测以正确触发事件：) if ("createEvent" in document) { var evt = document.createEvent("HTMLEvents"); evt.initEvent("change", false, true); element.dispatchEvent(evt); } else element.fireEvent("onchange");