为什么此Javascript代码未写入网页？

Question

I have just started learning Javascript. 我刚刚开始学习Javascript。 I want "Hello World!" 我想要“ Hello World！” to be written to a webpage once a user clicks a button. 用户单击按钮后将其写入网页。 I have tried this: 我已经试过了：

<html>
<head>
<script type="text/javascript">
function displaymessage()
{
document.write("Hello World!");
}
</script>
</head>

<body>
<form>
<input type="button" value="Click me!" onclick="displaymessage()" />
</form>
</body>
</html>

I can get it to do a window.alert("Hello World!") but not do document.write("Hello World!") for some reason. 由于某种原因，我可以使它执行window.alert("Hello World!")但不能执行document.write("Hello World!") 。 What happens is the button disappears and no text is displayed. 发生的情况是按钮消失并且没有文本显示。 My guess is that the problem is in the document.write but I do not know how to work around it. 我的猜测是问题出在document.write但我不知道如何解决。 Any suggestions? 有什么建议么？

Answer 1

Because the document has already been written at that point. 因为那时文档已经写好了。 You can set text like so: 您可以这样设置文本：

<button id="lol">blah</button>
<script>
    function setText( obj, to ) {
        obj.textContent? obj.textContent = to : obj.innerText = to;
    }
    var lol = document.getElementById('lol')

    lol.onclick = function() {
        var p = document.createElement('p');
        document.body.appendChild(p);
        setText( p, 'hi' );
    }
</script>

Another popular but often looked down technique would be innerHTML . 另一种流行但经常被忽视的技术是innerHTML 。

Answer 2

Document.write is used to write to the currently loading HTML file. Document.write用于写入当前正在加载的HTML文件。 Once the page has been loaded, and a user begins interacting with the page, document.write is useless. 一旦页面被加载，并且用户开始与页面进行交互，document.write就没有用了。

为什么此Javascript代码未写入网页？

问题描述

2 个解决方案

解决方案1
5 已采纳 2010-06-20 00:09:59

解决方案2
2 2010-06-20 00:12:54

为什么此Javascript代码未写入网页？

问题描述

2 个解决方案

解决方案1 5 已采纳 2010-06-20 00:09:59

解决方案2 2 2010-06-20 00:12:54

解决方案1
5 已采纳 2010-06-20 00:09:59

解决方案2
2 2010-06-20 00:12:54