We often use code like javascript:void(0), so what does javascript:void(0) mean in JavaScript? The most critical thing in
javascript:void(0) is the void keyword. void is a very important keyword in JavaScript. This operator specifies to calculate an expression but does not return a value.
The syntax format is as follows:
<head> <script type="text/javascript"> <!-- void func() javascript:void func() 或者 void(func()) javascript:void(func()) //--> </script> </head>
The following code creates a hyperlink, and nothing will happen when the user clicks it.
<a href="javascript:void(0)">单击此处什么也不会发生</a>
void(0) evaluates to 0 when user links, but has no effect on Javascript.
In the following example, a warning message is displayed after the user clicks the link:
<head> <script type="text/javascript"> <!-- //--> </script> </head> <body> <a href="javascript:void(alert('Warning!!!'))">点我!</a> </body>
In the following example, parameter a will return undefined:
<head>
<script type="text/javascript">
<!--
function getValue(){
var a,b,c;
a = void ( b = 5, c = 7 );
document.write('a = ' + a + ' b = ' + b +' c = ' + c );
}
//-->
</script>
</head>The difference between href="#" and href="javascript:void(0)"
# Contains a location information. The default anchor is #top, which is the top of the web page.
And javascript:void(0), just means a dead link.
When the page is very long, # will be used to locate the specific location of the page. The format is: # + id.
If you want to define a dead link please use javascript:void(0).
<a href="javascript:void(0);">点我没有反应的!</a> <a href="#pos">点我定位到指定位置!</a> <br> ... <br> <p id="pos">尾部定位点</p>
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