# startsWith method

bool startsWith (Pattern pattern, [ int index = 0 ])

Returns true if this string starts with a match of `pattern`.

    var string = 'Dart';
    string.startsWith('D');                       // true
    string.startsWith(new RegExp(r'[A-Z][a-z]')); // true

If `index` is provided, this method checks if the substring starting at that index starts with a match of `pattern`:

    string.startsWith('art', 1);                  // true
    string.startsWith(new RegExp(r'\w{3}'));      // true

`index` must not be negative or greater than length.

A RegExp containing '^' does not match if the `index` is greater than zero. The pattern works on the string as a whole, and does not extract a substring starting at `index` first:

    string.startsWith(new RegExp(r'^art'), 1);    // false
    string.startsWith(new RegExp(r'art'), 1);     // true

## Implementation

    bool startsWith(Pattern pattern, [int index = 0]);