求一超简单的正则表达式

Question

要求验证信息
为数字0-100

Answer 1

\b((?=\d\d\d)100|[1-9]\d|\d)\b测试工具：（推荐）
http://www.regexlab.com/zh/workshop.asp?pat=%5Cb0*%28%28%3F%3D%5Cd%5Cd%5Cd%29100%7C%5B1-9%5D%5Cd%7C%5Cd%29%5Cb&txt=0%20%20ok%0D%0A1%20%20ok%0D%0A01%20ok%0D%0A10%20ok%0D%0A90%20ok%0D%0A090%20%20ok%0D%0A100%20%20ok%0D%0A101%0D%0A1000&dlt=0

Answer 2

Regex.IsMatch(str,@"^([0-9]{1,1}|[0-9]{2,2}|100)$");