jQuery implements the case-insensitive method of contains method_jquery

The example in this article describes how jQuery implements the contains method to be case-insensitive. Share it with everyone for your reference. The specific implementation method is 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')")

Test HTML file:

<div>john</div>
<div>John</div>
<div>hey hey JOHN hey hey</div>

I hope this article will be helpful to everyone’s jQuery programming.