javascript:void(0) Meaning
We often use code like javascript:void(0), so in JavaScript javascript:void What does (0) mean?
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>The following code creates a hyperlink that does nothing when the user clicks on it.<script type="text/javascript">
<!--
void func()
javascript:void func()
or
void(func())
javascript:void(func())
//-->
</script>
</head>
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文网(php.cn)</title> </head> <body> <a href="javascript:void(0)">单此处什么也不会发生</a> </body> </html>When the user links, void(0) evaluates to 0, but has no effect on Javascript. In the following example, a warning message is displayed after the user clicks the link:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文网(php.cn)</title> <script type="text/javascript"> <!-- //--> </script> </head> <body> <p>点击以下链接查看结果:</p> <a href="javascript:void(alert('Warning!!!'))">点我!</a> </body> </html>Run the program and try it
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文网(php.cn)</title> <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> <body> <p>点击以下按钮查看结果:</p> <form> <input type="button" value="点我" onclick="getValue();" /> </form> </body> </html>Run the program and try it
The difference between href="#" and href="javascript:void(0)"
# Contains With a location information, the default anchor is #top, which is the top of the web page. And javascript:void(0) only represents 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).Example
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文网(php.cn)</title> </head> <body> <a href="javascript:void(0);">点我没有反应的!</a><br/> <a href="#pos">点我定位到指定位置!</a> <br> ... <br> <p id="pos">尾部定位点</p> </body> </html>Run the program and try it