alpha numeric validation is not working

Question

For a Angular 2 application, I wrote a custom validator TypeScript class like below,

import { FormControl } from '@angular/forms';

export class AlphaNumericValidator {
    static invalidAlphaNumeric(control: FormControl): { [key: string]: boolean } {
        if (control.value.length && !control.value.match(/^[a-z0-9]+$/i)) {
            return { invalidAlphaNumeric: true };
        }
        return null;
    }
}

I am applying this validator for a Model Driven Form,

'name': [this.exercise.name, [Validators.required, AlphaNumericValidator.invalidAlphaNumeric]],

And Here is the HTML,

<label *ngIf="exerciseForm.controls.name.hasError('invalidAlphaNumeric') && (exerciseForm.controls.name.touched || submitted)" class="alert alert-danger validation-message">Name must be alphanumeric</label>

I notice that whenever I am typing a character in input, the above TypeScript class code called, but every time it's return Null.

Is there any issue on typeScript class?

Thanks!

Can only be because `control.value.match(/^[a-z0-9]+$/i)` always matches — Günter Zöchbauer, Feb 22 '17 at 15:36
What do you get when you add `console.log(control.value.match(/^[a-z0-9]+$/i));` before th `if(...)`? — Günter Zöchbauer, Feb 22 '17 at 15:43
You could try `/^[a-z0-9]+$/i.test(control.value)` instead http://stackoverflow.com/questions/6603015/check-whether-a-string-matches-a-regex — Günter Zöchbauer, Feb 22 '17 at 15:49
i tried this, but now even for valid alphanumeric values, error message always appreas — user584018, Feb 22 '17 at 15:57

score 0 · Accepted Answer · answered Feb 22 '17 at 15:50

0

use

!/^[a-z0-9]+$/i.test(control.value)

to get a boolean result

answered Feb 22 '17 at 15:50

Günter Zöchbauer

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i tried this, but now even for valid alphanumeric values, error message always appreas – user584018 Feb 22 '17 at 15:58
Can't reproduce. This works fine in the browser console like `!/^[a-z0-9]+$/i.test('abc')` (`false`) or `!/^[a-z0-9]+$/i.test('ab.)` (`true`) – Günter Zöchbauer Feb 22 '17 at 16:01
will it be possible that one character should be number and one character should be non-number? – user584018 Feb 22 '17 at 16:07
Can you please be more specific? What exactly do you want to allow/disallow? – Günter Zöchbauer Feb 22 '17 at 16:08
for input "abc" should be true, for "234" also true, but for "7Alph" should false. the input content must contain at lease a character and a number – user584018 Feb 22 '17 at 16:11
@GünterZöchbauer what about strictly Alpha (uppercase and or lowercase) or Strictly numeric characters? Something like `/(^[a-z]+$)|(^[A-Z]+$)/i` Not sure? – Ben Racicot Aug 27 '17 at 00:43

alpha numeric validation is not working

1 Answers1