Check whether a string starts with a given pattern.
The startsWith method returns true if the string begins with the specified pattern at the given index. The pattern can be a String or a RegExp. An optional index parameter specifies the position in the string from which to check.
This is commonly used for prefix checking, routing logic, or filtering collections of strings. When the index parameter is provided, the method checks whether the pattern matches at that specific position rather than at the beginning of the string.
The check is case-sensitive. For case-insensitive prefix matching, convert both the string and the pattern to the same case using toLowerCase or toUpperCase before comparing.
| Name | Description | Optional |
|---|---|---|
pattern |
The Pattern (String or RegExp) to check at the start. | No |
index |
The index position to start checking from. Defaults to 0. | Yes |
print('Dart is great'.startsWith('Dart')); // true
print('Dart is great'.startsWith('great')); // false
print('Dart is great'.startsWith('is', 5)); // true