I am having trouble figuring out how to write a regex to match a number (technically a string) with the following rules:
我不知道如何编写一个regex来将数字(技术上是字符串)与以下规则匹配:
- all numeric
- 所有的数字
- must be exactly 11 digits
- 一定是11位吗
- it must start with at least 2 zeros
- 它必须至少从2个0开始
- it may not start with more than 4 zeros
- 开始时可能不超过4个零
I can use \d{11} to match for the exactly 11 digits, and ^0{2,4] to match the leading zeros part, but I can't figure out how to combine them.
我可以使用\ d { 11 }匹配11位数,^ 0 { 2,4]匹配前导零的部分,但我不知道如何将它们组合起来。
1 个解决方案
#1
3
^00(?!000)\d{9}$
It checks for two zeroes and then checks that there are not more than 2 0's following it.
if it is not it checks the other 9 numbers to the end of the string.
它检查两个0，然后检查后面不超过2个0。如果不是，它会检查字符串末尾的其他9个数字。
This assumes your engine supports lookaheads.
这假定您的引擎支持lookahead。
#1
3
^00(?!000)\d{9}$
It checks for two zeroes and then checks that there are not more than 2 0's following it.
if it is not it checks the other 9 numbers to the end of the string.
它检查两个0，然后检查后面不超过2个0。如果不是，它会检查字符串末尾的其他9个数字。
This assumes your engine supports lookaheads.
这假定您的引擎支持lookahead。