description

# convert method Null safety

Uint8List convert (

1. String string,
2. [int start = 0,
3. int? end]

)
inherited

Converts the String into a list of its code units.

If `start` and `end` are provided, only the substring `string.substring(start, end)` is used as input to the conversion.

## Implementation

    Uint8List convert(String string, [int start = 0, int? end]) {
      var stringLength = string.length;
      end = RangeError.checkValidRange(start, end, stringLength);
      // TODO(38725): Remove workaround when assignment promotion is implemented
      if (end == null) {
        throw RangeError("Invalid range");
      }
      var length = end - start;
      var result = Uint8List(length);
      for (var i = 0; i < length; i++) {
        var codeUnit = string.codeUnitAt(start + i);
        if ((codeUnit & ~_subsetMask) != 0) {
          throw ArgumentError.value(
              string, "string", "Contains invalid characters.");
        }
        result[i] = codeUnit;
      }
      return result;
    }