Php implementation of jQuery extension function _ PHP Tutorial

Php implements jQuery extension functions. This is the contains function. The book introduces that this function filters the selected element set based on the element content. when I run the code, it always reports an error, later I found that the contains function is not in the function library. The book says that this function filters the selected element set based on the element content. when I run the code, I always report an error, later I found that this function is not in the function library, so I wrote this function myself.
The code is as follows:

The code is as follows:

Function yhCheckIsIncludingValue (element, pattern)
{
Var bool = false;
Var childrenNodes = element. childNodes;
If (childrenNodes. length = 0)
{
If (element. nodeValue! = Null)
{
If (pattern.exe c (element. nodeValue )! = Null)
{
Return true;
}
}
}
If (childrenNodes. length! = 0)
{
For (var I = 0; I <childrenNodes. length; I ++)
{
If (bool = yhCheckIsIncludingValue (childrenNodes, pattern) break;
}
}
Return bool;
}
// Apply this function in the function chain
$. Fn. contains = function (text)
{
Var text = $. trim (text );
If (text = 'undefined') return this;
Var pattern = new RegExp (text, 'I ');
Return this. filter (function (){
Return yhCheckIsIncludingValue (this, pattern );
});
}

It runs normally on IE. I don't know what will happen to other browsers?

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