Question

May someone please put some light on this regex…It looks so difficult to understand…

/^[0-9]{1,}((\.){1}[0-9]{1,}){0,1}$/.test(value)

Value is what I send from the text box to validate…

Answer 1

^           // start with
[0-9]{1,}   // one or more of 0-9
(
  (\.){1}   // a period
  [0-9]{1,} // one or more of 0-9 
){0,1}      // zero or one of this group
$           // until end

Or even shorter:

^[0-9]+((\.)[0-9]+)?$

i.e. a series of digits optionally followed by a period character and a series of digits.

So anything like

0011221100
12345
1.23456
0.0
0000.1111

will match.