问题
I want to validate password entered by user for following criteria :
Password should be at least 8 characters long and should contain one number,one character and one special character.
For it I used following regular expression :
^(?=.*[A-Za-z])(?=.*\d)(?=.*[$@$!%*#?&])[A-Za-z\d$@$!%*#?&]{8,}$
I tried this expression in my angularjs code as below :
<md-input-container class="md-block" style="margin-top:0px;">
<label>Password</label> <md-icon
md-svg-src="/images/icons/ic_lock_black_24px.svg" class="name"></md-icon>
<input type="password" ng-model="newUser.userPassword"
name="userPassword" required
ng-pattern="^(?=.*[A-Za-z])(?=.*\d)(?=.*[$@$!%*#?&])[A-Za-z\d$@$!%*#?&]{8,}$">
<div
ng-messages="registerForm.userPassword.$error">
<div ng-message="pattern">Password should be atleast 8 characters long
and should contain one number,one character and one special
character</div>
<div ng-message="required">Password should be atleast 8 characters
long and should contain one number,one character and one special
character</div>
</div>
</md-input-container>
In my above code the error message displays when the password field is blank and focus is lost. If user enters a password which doesn't satisfy the criteria I mentioned the error message doesn't show up.
How should I fix this issue? Somebody please help me.
回答1:
As far as i understood your problem. Check your console It might be broken on lexical errors.
You forgot slash at start and at end of ng-pattern.
Please use ng-pattern="/^(?=.*[A-Za-z])(?=.*\d)(?=.*[$@$!%*#?&])[A-Za-z\d$@$!%*#?&]{8,}$/"
I have created a plunk which might help you. https://plnkr.co/edit/qCjp6a?p=preview
回答2:
Just a couple notes
1) The above contains one redundant $. It should be ng-pattern="/^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$/"
2) Don't remove leading ^ and trailing $ as it prevents from entering white spaces
3) If you want to define the pattern in controller then
$scope.passwordStrength = /^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$/; and <input ng-pattern="passwordStrength">
but never
$scope.passwordStrength = "/^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$/";
as the pattern is a RegExp object, not a string.
Hope this will help you save some time.
回答3:
I took a stab at this with Angular's built-in pattern validator and was able to come up with the following that checks for:
- At least 8 characters in length
- Lowercase letters
- Uppercase letters
Numbers Special characters
password: [ '', [ Validators.required, Validators.pattern('(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[$@$!%*?&])[A-Za-z\d$@$!%*?&].{8,}') ] ]
I'll add that I'm by no means a regex expert. This is simply what worked for me for a closely related case to the OP. Maybe it will help someone else. Mozilla's documentation helped a lot in figuring this out, specifically the Writing a regular expression pattern section.
来源：https://stackoverflow.com/questions/36352562/how-to-add-password-validation-using-regular-expression-in-angularjs-according-t