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i need help with java regex!?
for form validation
i need to only accept input that java can interpret as a float since im saving the input into a float variable
such as:
123
123.456
and not:
123.
.
abcd
!@#$%&
thanks!
1 Answer
- ?Lv 77 years agoFavorite Answer
why not get the specification for a float and build it from that? it's complicated.
you forgot for instance scientific format.
you also forgot that floats can be
optional signs followed by
integer
.frac
integer.frac
any combination of above followed by e followed by optional signs followed by decimal digits OR
integer.fracP
followed by P followed by optional sign followed by decimal digits.
where integer and frac must be same kind of number base (like octal) and in the case of e, digits must be decimal digits (base 10).
well, here it is. you will have to take the spaces out, YA truncates without them.
([+-]*(\d+|\.\d+ | \d+\.\d+) ([Ee][+-]*\d+)? | (0[xX][0-9A-Fa-f]+(\.[0-9A-Fa-f])? | 0[0-7]+(\.[0-7]+)? | [1-9]\d*(\.\d+)?)[pP]\d+)
I think with p that it only allows and also requires 1 digit left of period(.). so it may be instead
([+-]*(\d+|\.\d+ | \d+\.\d+) ([Ee][+-]*\d+)? | (0[xX][0-9A-Fa-f]\.[0-9A-Fa-f] | 0[0-7]\.[0-7]+ | [1-9]\.\d+)[pP]\d+)
and now there's a p that's a new part of the new IEEE 754 floating point representation I think. look under basic data types and literals under javadoc.
http://docs.oracle.com/javase/8/docs/api/index.htm...
if you are doing javascript form validation using pattern="", make sure you replace any \d with [0-9]
