Two methods of javascript customizing startWith() and endWith()_javascript skills

1. Use regular expressions to implement startWith and endWith effect functions

Copy code The code is as follows:

String.prototype.startWith=function(str){
var reg=new RegExp("^" str);
return reg.test(this);
}
//Test ok, directly Just use str.endWith("abc") to call
String.prototype.endWith=function(str){
var reg=new RegExp(str "$");
return reg.test( this);
}

2. JavaScript implements startWith and endWith effect functions

Copy code The code is as follows:

<script type="text/javascript">
String.prototype.endWith=function(s){
if(s==null|| s==""||this.length==0||s.length>this.length)
return false;
if(this.substring(this.length-s.length)==s)
return true;
else
return false;
return true;
}
String.prototype.startWith=function(s){
if(s==null| |s==""||this.length==0||s.length>this.length)
return false;
if(this.substr(0,s.length)==s)
return true;
else
return false; href;
if (url.startWith('http://www.jb51.net'))
{
//If the current url starts with http://www.jb51.net/
}