js get first four characters in string code example

Example 1: javascript get first 2 char

String.substring(0, 2);
//Return the first two characters of the string
//First parameter is the starting index, 0 corresponding to the first character
//Second parameter is the number of character to return

Example 2: javascript substring

// zero-based index, 'end' is excluded from result
myString.substring( start, end )