Obtain the url parameter value of a page using a Javascript regular expression.

We will introduce how to directly use js to obtain URL parameter values. js cannot have system functions available like php, asp, and jsp, if you want to use js to obtain the page url parameter value, we need to use a regular expression. The following is an introduction.

Obtain url parameters:

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Function getURLParam (name ){ Var value = location. search. match (new RegExp ("[? &] "+ Name +" = ([^ &] *) (&?) "," I ")); Return value? DecodeURIComponent (value [1]): value; }

Add parameters to the url:

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Function addURLParam (url, name, value ){ Url + = (url. indexOf ("? ") =-1? "? ":"&"); Url + = encodeURIComponent (name) + "=" + encodeURIComponent (value ); Return url; }

Method 2: Regular Expression Analysis

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Function getQueryString (name ){ Var reg = new RegExp ("(^ | &)" + name + "= ([^ &] *) (& | $)", "I "); Var r = window. location. search. substr (1). match (reg ); If (r! = Null) return unescape (r [2]); return null; }

Call this method as follows:

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Alert (GetQueryString ("parameter name 1 ")); Alert (GetQueryString ("parameter name 2 ")); Alert (GetQueryString ("parameter name 3 "));