c# - Why does this Regex match? -

i have written regular expression match following criteria

• any digit (0-9)
• hyphen
• whitespace
• in order
• length between 10 , 25

([0-9\-\w]{10,25})

i using detect payment card numbers, works:

regex.ismatch("34343434343434", "([0-9\\-\\w]{10,25})"); // true 

but works:

regex.ismatch("logmethodcomplete", "([0-9\\-\\w]{10,25})"); // true 

what doing wrong?

this c#

take @ regular expression language - quick reference, section character classes.

\w matches word character including underscore, not whitespace.

to match whitespace, can use \s.

to match digits, can use \d.