Run your page again and notice that you now have to click on an image to get the alert box to pop up.

再次运行页面并注意，现在必须要单击每个图像以弹出警告框。

youdao

Now, if you run the form, you'll still see the alert box, but only once, because the new value is allowable according to the schema.

这时再运行表单，我们仍然会看到警示框，不过它只会出现一次，因为根据模式新值是允许输入的。

youdao

In Listing 4, if valid is returned as false, an alert box will open, and the link will not be followed, as the event handler has returned a false value.

在清单4中，如果valid返回false，将打开一个警告框，链接不会被遵循，因为事件处理程序返回一个false值。

youdao

Not only will Twitter notify users that a request has been made to remove content they published on Twitter, it will also show an alert box to people in the country where the content is blocked.

FORBES: Twitter and the Dictator's Dilemma