The following functions are used to extract the character in the string to the left or to the right. Left(), Right() functions are not available in Javascript.

 function Left(str, n){	if (n <= 0)	    return "";	else if (n > String(str).length)	    return str;	else	    return String(str).substring(0,n);}function Right(str, n){    if (n <= 0)       return "";    else if (n > String(str).length)       return str;    else {       var iLen = String(str).length;       return String(str).substring(iLen, iLen - n);    }}