Numbers to words translator

Requirements

1. Translation is for positive integer values between 0 and 9999
2. Translation is required for English language only
3. To be written using C#
4. Any type of UI for the translator is permitted

Additional optional requirements

1. Translation can be extended to apply to decimal values, limited to 2 decimal places

Testing

1. When converting zero, the output should be zero
2. When input is 1234, the output should be one thousand, two hundred and thirty-four
3. Special cases where "missing" elements should be handled correctly:
4. When the input is 1001, the output should be one thousand and one
5. When the input is 2300, the output should be two thousand, three hundred