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RegEx for strong password

Posted By:      Posted Date: September 08, 2010    Points: 0   Category :.NET Framework
Hi I need  RegEx expression for the following: Passwords must be at least eight characters including at least one number and one special character (punctuation, symbol or upper/lower case character).  Note: The  RegEx will be used in .NET   Thanks much!

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I'm trying to validate a password, and I'm almost there, but need some help finishing it off. Here's what I need:

1) 6-10 characters

2) At least one alpha AND one number

3) The following special chars are allowed (0 or more): !@#$%

Here's what I have:


Passwords that should work: test1ng, abc123, abc1234567, 123abc, abc!123, !@#$%1abcd, !@#$%a9

Passwords that shouldn't work: a, 1, a1, 1$, %, abc!@#, 012345, a1234+, abcde, test*ng, abcde!, !@#$%!, a1234567890, testit!0987, 1abcdefghij

It works on all my test cases, except it allows "a1234567890", "testit!0987", and "1abcdefghij", none of which should be allowed, since they contain more than 10 chars. What am I missing?

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I have a requirment where in the password field should accept all keys except space, it should have atleast one number , length should be 6 to 50
I tried following but did not work
1) Regex = @"^.*(?=.{6,50})(?=.*\d)(?=.*[a-zA-Z]).*$"

2) ^(?=[^\s])(?=[^\s]{6,50})(?=[^\s]*\d)(?=[^\s]*[a-zA-Z]).*$

Following are my test input text ( test case no 2 is having space at end)

ShouldNOT 654321-4
Should NOT654321-5
S houldNOT654321-6
ShouldNOT65432 1-7
S houldNOT 654321-9

Please help.

Thanks in Advance.
Rajendra Dewani

Regards Rajendra Dewani

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