Flash Player 5.
my_str.indexOf(substring,[startIndex])
substring An integer or string specifying the substring to be searched for within my_str.
startIndex An integer specifying the starting point in my_str to search for substring. This parameter is optional.
The position of the first occurrence of the specified substring, or -1.
Method; searches the string and returns the position of the first occurrence of the specified substring. If the value is not found, the method returns -1.