# setCharAt method

void setCharAt(

1. int index,
2. String char

)

Sets the character at the specified index.

`index` the index `char` the new character

## Implementation

    void setCharAt(int index, String char) {
      if (char.length != 1) {
        throw InvalidArgumentException('Must be a single character');
      }

      String current = _buffer.toString();
      if (index < 0 || index >= current.length) {
        throw RangeError('Index out of range: $index');
      }

      String before = current.substring(0, index);
      String after = current.substring(index + 1);

      _buffer.clear();
      _buffer.write(before);
      _buffer.write(char);
      _buffer.write(after);
    }