正则表达式用于验证固定范围的十进制数字

Question

I require a regex to validate fixed range decimal numbers eg 1234.1234 - valid, 4444.1234 - valid 123.123 - invalid, 1234.123 - invalid

The number 4 digit before decimal and 4 digit after decimal only valid. I'm currently uses this regex - /^\\S((\\d{4})((\\.\\d{4})?))$/ but this not satisfies me.

Answer 1

^\d{4}(\.\d{4})?$

This should do it for you.Use

^[1-9]\d{3}(\.\d{4})?$

If you dont want to match 0234.1234

Answer 2

You can use this regex:

/^\d{4}(?:\.\d{4})?$/

This will match 1234 or 1234.5678 as valid matched.

RegEx Demo