将“return false"添加到单击事件侦听器有什么影响? [英] What's the effect of adding 'return false' to a click event listener?

问题描述

我多次在 HTML 页面中看到过这样的链接:

Many times I've seen links like these in HTML pages:

<a href='#' onclick='someFunc(3.1415926); return false;'>Click here !</a>

里面的return false有什么作用?

此外，我通常不会在按钮中看到这一点.

Also, I don't usually see that in buttons.

这是在任何地方指定的吗?在 w3.org 的某些规范中?

Is this specified anywhere? In some spec in w3.org?

推荐答案

事件处理程序的返回值决定了是否也应该发生默认浏览器行为.在点击链接的情况下，这将是跟随链接，但区别在表单提交处理程序中最为明显，如果用户输入信息有误，您可以取消表单提交.

The return value of an event handler determines whether or not the default browser behaviour should take place as well. In the case of clicking on links, this would be following the link, but the difference is most noticeable in form submit handlers, where you can cancel a form submission if the user has made a mistake entering the information.

我不相信有 W3C 规范.像这样的所有古老的 JavaScript 接口都被赋予了DOM 0"的绰号，而且大多是未指定的.您可能有幸阅读旧的 Netscape 2 文档.

I don't believe there is a W3C specification for this. All the ancient JavaScript interfaces like this have been given the nickname "DOM 0", and are mostly unspecified. You may have some luck reading old Netscape 2 documentation.

实现这种效果的现代方法是调用 event.preventDefault()，这在 DOM 2 事件规范.

The modern way of achieving this effect is to call event.preventDefault(), and this is specified in the DOM 2 Events specification.

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