jquery implementation contains method case-insensitive method _jquery

The example of this article describes the method of jquery implementation contains method is case-insensitive. Share to everyone for your reference. The implementation methods are as follows:

NEW selector  
jquery.expr[': '. Contains = function (A, I, m) {return
 jQuery (a). Text (). toUpperCase ().
   indexOf (M[3].touppercase ()) >= 0;
};  
 
//overwrites old Selecor
jquery.expr[': '].contains = function (A, I, m) {return
 jQuery (a). Text (). toUpperCase ()
   . IndexOf (M[3].touppercase ()) >= 0;
};

Usage:

$ ("Div:contains (' John ')")

To test an HTML file:

<div>john</div>
<div>John</div>
<div>hey Hey John Hey hey</div>

I hope this article will help you with your jquery programming.