<scripttype="text/javascript">

Array.prototype.insert=function(vVal,nIdx){

vararrTemp=this;

if(nIdx>arrTemp.length)nIdx=arrTemp.length;

if(nIdx<-arrTemp.length)nIdx=0;

if(nIdx<0)nIdx=arrTemp.length+nIdx;

for(varii=arrTemp.length;ii>nIdx;ii--){

arrTemp[ii]=arrTemp[ii-1];

}

arrTemp[nIdx]=vVal;

returnarrTemp;

}

vararr=["w","w","w","i","e","c","n","n","e","t"];

alert(arr.join(""));

arr.insert(".",3);

alert(arr.join(""));

arr.insert(".",-3);

alert(arr.join(""));

</script>