我们可以将所有所有信息作为参数传递给内联事件处理程序吗？

Question

I found this code on internet where author is passing id of the element as first parameter to the event handler. 我在互联网上找到了此代码，作者将元素的id作为第一个参数传递给事件处理程序。 Refer to the sample below. 请参阅下面的示例。

Until today, I was under the impression that we can pass only event information as argument to the event handler and I can see that we can pass id of current element also as parameter to event handler. 直到今天，我的印象是我们只能将event信息作为参数传递给事件处理程序，并且可以看到我们也可以将当前元素的id作为参数传递给事件处理程序。

Where is this documented on MDN? 这在MDN上有何记载？ Can someone point to me the documentation? 有人可以指向我的文档吗？

<!DOCTYPE html>
<html>
    <head>
        <title></title>
    </head>
    <body>
        <input type="text" value="Hello" onchange="someFunction(id,event);" id="someId"/>
    </body>
    <script type="text/javascript">
        function someFunction(id,event){
            console.log(id); //Printing "someId"
            console.log(event.target.value); //It is printing updated value 
        }
    </script>
</html>

Answer 1

I believe you can refer to any property that's somewhere in the element's prototype chain as a standalone variable: 我相信您可以将元素原型链中某处的任何属性称为独立变量：

 function someFunction(id, onclick, children, clientTop) { console.log(id); // someId console.log(onclick); // note, this is null, not undefined! console.log(children); // length 0, but still an HTMLCollection console.log(clientTop); // 2 }

 <input type="text" value="Hello" onchange="someFunction(id, onclick, children, clientTop);" id="someId" />

It's as if the inline handler is wrapped in a with(this) . 就像将内联处理程序包装在with(this) 。 Referencing a property name that exists on the element object, or in the element's prototype chain, will result in that property value being referenced. 引用元素对象或元素原型链中存在的属性名称，将导致该属性值被引用。

So, an inline handler like 因此，像

<input onchange="somestr">

is interpreted something like 被解释为

// assume this refers to that input element:
with (this) {
  eval(somestr);
}

Note that event is in a different category - it's not a property of the element, it's a global window.event . 请注意， event属于不同的类别-它不是元素的属性，而是全局window.event 。

我们可以将所有所有信息作为参数传递给内联事件处理程序吗？

问题描述

1 个解决方案

解决方案1
2 已采纳 2019-01-01 01:24:49

我们可以将所有所有信息作为参数传递给内联事件处理程序吗？

问题描述

1 个解决方案

解决方案1 2 已采纳 2019-01-01 01:24:49

解决方案1
2 已采纳 2019-01-01 01:24:49