jquery's method grep() implements array filtering
This time I will bring you the jquery method grep() to implement arrayfiltering, and the jquery method grep() to implement array filteringNotesWhat are they? Here are actual cases. Let’s take a look.
How to use grep():
grep(array,callback,invert)
array: array to be filtered;
callback: Process each element in the array and filter the elements. This function contains two parameters, the first is the value of the current array element, and the other is the subscript of the current array element, that is, the element index value. This function should return a boolean value. Alternatively, this function can be set to a string, which, when set to a string, is treated as a "lambda-form" (short form?), where a represents the array element and i represents the element index value. For example, "a > 0" represents "function(a){ return a > 0; }"
invert: Boolean optional, the default value is false, the value is true or false , if "invert" is false or set, the function returns the elements in the array that are returned true by the filter function. When "invert" is true, the function returns the set of elements that are returned false by the filter function.
After explaining the usage of grep(), let’s give a small example:
var arr=$.grep([0,1,2,3,4,5,6],function(n,i){ return n>2});
The above example returns [3,4,5,6], but we The value given to invert is true, for example
Copy code The code is as follows:
var arr=$.grep([0,1,2,3,4,5,6],function(n,i){ return n>2 },ture);
So what is returned now is [0,1,2], that is Elements filtered out by the callback function.
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
Recommended reading:
Detailed explanation of the steps for jQuery ajax to call WCF service
Summary of jQuery method of getting page width and height
The above is the detailed content of jquery's method grep() implements array filtering. For more information, please follow other related articles on the PHP Chinese website!

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