我正在学习编写JavaScript代码。在这个脚本中,我想要一个链接不去其指定的位置,但改变段落之前的文本。我已经创建了一个函数来实现它onclick
,但是该函数不能返回false。
<html>
<head>
<title>Javascript Test #6</title>
<script type="text/javascript">
document.getElementById("links").onclick=writeData();
function writeData()
{
document.getElementById("para").innerHTML="Changed Paragraph Content";
return false;
}
</script>
</head>
<body>
<p id="para">Unchanged Paragraph Content</p>
<br/>
<a id="links" href="javascript-return.html"> Click here to change the paragraph content </a>
</body>
</html>
document.getElementById("links").onclick=writeData;
不要使用括号。它们迫使你的函数求值。但是你想给函数赋值
编辑:当然,你需要在文档加载之后赋值你的函数。现在的方式是,在执行赋值时不会有id为links
的元素。基本上,只要把你的脚本块放在links
元素下面。
<html>
<head>
<title>Javascript Test #6</title>
</head>
<body>
<p id="para">Unchanged Paragraph Content</p>
<br/>
<a id="links" href="javascript-return.html"> Click here to change the paragraph content </a>
<script type="text/javascript">
document.getElementById("links").onclick=writeData;
function writeData()
{
document.getElementById("para").innerHTML="Changed Paragraph Content";
return false;
}
</script>
</body>
</html>
EDIT (Using window.onload):
<html>
<head>
<title>Javascript Test #6</title>
<script type="text/javascript">
window.onload = function() {
document.getElementById("links").onclick=writeData;
}
function writeData()
{
document.getElementById("para").innerHTML="Changed Paragraph Content";
return false;
}
</script>
</head>
<body>
<p id="para">Unchanged Paragraph Content</p>
<br/>
<a id="links" href="javascript-return.html"> Click here to change the paragraph content </a>
</body>
</html>
处理文档时。getElementById,您应该确保在调用时,元素在DOM中。只需使用内联点击处理程序:
<html>
<head>
<title>Javascript Test #6</title>
<script type="text/javascript">
function writeData()
{
document.getElementById("para").innerHTML="Changed Paragraph Content";
return false;
}
</script>
</head>
<body>
<p id="para">Unchanged Paragraph Content</p>
<br/>
<a id="links" href="javascript-return.html" onclick="return writeData();"> Click here to change the paragraph content </a>
</body>
</html>
或者,改变事情的顺序:首先准备好DOM,然后,插入你的js脚本:
<html>
<head>
<title>Javascript Test #6</title>
</head>
<body>
<p id="para">Unchanged Paragraph Content</p>
<br/>
<a id="links" href="javascript-return.html" onclick="return writeData();"> Click here to change the paragraph content </a>
<script type="text/javascript">
document.getElementById("links").onclick=writeData;
function writeData()
{
document.getElementById("para").innerHTML="Changed Paragraph Content";
return false;
}
</script>
</body>
</html>
在这里看到它的作用:http://jsfiddle.net/2CpcF/