Beginner prototype, send a JS to accept the URL parameters of the code _prototype

<textarea id="runcode16032"><script> function Request (key) {if (typeof (This) = "undefined") return false; if (this.length>0) {var s = this.split ("&"); for (var i in s) {var sp=s[i].split (' = ') if (Sp[0]==key) return (sp[1]); return false; else return false} function Getallkey () {if (typeof (This) = "undefined") return false; var arr=new Array; if (this.length>0) {var s = this.split ("&"); for (var i in s) {var sp=s[i].split ("="); Arr.push (Sp[0]); return arr; else return false} string.prototype.request=request String.prototype.getallkey=getallkey//====================== ============================= var url=location.search.substr (1)//action=reply&forum=3&topic=1469 var arg= Url.getallkey () alert (ARG) document.write (submit parameter: +arg) for (var cou in Arg) document.write (the value of the argument "+arg[cou]+" is: "+URL.R Equest (Arg[cou]) + "") </script></textarea>
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