substr Method
Returns a substring beginning at a specified location and having a specified length.
function substr(start : Number [, length : Number]) : String
Arguments
start
Required. The starting position of the desired substring. The index of the first character in the string is zero.length
Optional. The number of characters to include in the returned substring.
Remarks
If length is zero or negative, an empty string is returned. If not specified, the substring continues to the end of the string.
Example
The following example illustrates the use of the substr method.
function SubstrDemo(){
var s = "The quick brown fox jumps over the lazy dog.";
var result = s.substr(10, 5);
// Returns "brown".
return(result);
}