I have a simple form that needs to validate if the beginning and the end of the input is not space.
In HTML5, I will do this:
<input type="text" pattern="^(?!\s|.*\s$).*$">
What is the right property for validation pattern in the new Angular 2 ngControl directive? The official Beta API is still lacking documentation on this issue.
Now, you don't need to use FormBuilder and all this complicated valiation angular stuff. I put more details from this (Angular 2.0.8 - 3march2016):
https://github.com/angular/angular/commit/38cb526
Example from repo :
<input [ngControl]="fullName" pattern="[a-zA-Z ]*">
I test it and it works :) - here is my code:
<form (ngSubmit)="onSubmit(room)" #roomForm='ngForm' >
...
<input
id='room-capacity'
type="text"
class="form-control"
[(ngModel)]='room.capacity'
ngControl="capacity"
required
pattern="[0-9]+"
#capacity='ngForm'>
Validation is ONLY on server side. If something is wrong then server return error code e.g HTTP 400 and following json object in response body (as example):
this.err = {
"capacity" : "too_small"
"filed_name" : "error_name",
"field2_name" : "other_error_name",
...
}
In html template I use separate tag (div/span/small etc.)
<input [(ngModel)]='room.capacity' ...>
<small *ngIf="err.capacity" ...>{{ translate(err.capacity) }}</small>
If in 'capacity' is error then tag with msg translation will be visible. This approach have following advantages:
<small> tag)Of course sometimes I make exception if validation is needed on frontend side (e.g. retypePassword field on registration is never send to server).
Since version 2.0.0-beta.8 (2016-03-02), Angular now includes a Validators.pattern regex validator.
See the CHANGELOG
You could build your form using FormBuilder as it let you more flexible way to configure form.
export class MyComp {
form: ControlGroup;
constructor(@Inject()fb: FormBuilder) {
this.form = fb.group({
foo: ['', MyValidators.regex(/^(?!\s|.*\s$).*$/)]
});
}
Then in your template :
<input type="text" ngControl="foo" />
<div *ngIf="!form.foo.valid">Please correct foo entry !</div>
You can also customize ng-invalid CSS class.
As there is actually no validators for regex, you have to write your own. It is a simple function that takes a control in input, and return null if valid or a StringMap if invalid.
export class MyValidators {
static regex(pattern: string): Function {
return (control: Control): {[key: string]: any} => {
return control.value.match(pattern) ? null : {pattern: true};
};
}
}
Hope that it help you.
custom validation step by step
Html template
<form [ngFormModel]="demoForm">
<input
name="NotAllowSpecialCharacters"
type="text"
#demo="ngForm"
[ngFormControl] ="demoForm.controls['spec']"
>
<div class='error' *ngIf="demo.control.touched">
<div *ngIf="demo.control.hasError('required')"> field is required.</div>
<div *ngIf="demo.control.hasError('invalidChar')">Special Characters are not Allowed</div>
</div>
</form>
Component App.ts
import {Control, ControlGroup, FormBuilder, Validators, NgForm, NgClass} from 'angular2/common';
import {CustomValidator} from '../../yourServices/validatorService';
under class define
demoForm: ControlGroup;
constructor( @Inject(FormBuilder) private Fb: FormBuilder ) {
this.demoForm = Fb.group({
spec: new Control('', Validators.compose([Validators.required, CustomValidator.specialCharValidator])),
})
}
under {../../yourServices/validatorService.ts}
export class CustomValidator {
static specialCharValidator(control: Control): { [key: string]: any } {
if (control.value) {
if (!control.value.match(/[-!$%^&*()_+|~=`{}\[\]:";#@'<>?,.\/]/)) {
return null;
}
else {
return { 'invalidChar': true };
}
}
}
}
My solution with Angular 4.0.1: Just showing the UI for required CVC input - where the CVC must be exactly 3 digits:
<form #paymentCardForm="ngForm">
...
<md-input-container align="start">
<input #cvc2="ngModel" mdInput type="text" id="cvc2" name="cvc2" minlength="3" maxlength="3" placeholder="CVC" [(ngModel)]="paymentCard.cvc2" [disabled]="isBusy" pattern="\d{3}" required />
<md-hint *ngIf="cvc2.errors && (cvc2.touched || submitted)" class="validation-result">
<span [hidden]="!cvc2.errors.required && cvc2.dirty">
CVC is required.
</span>
<span [hidden]="!cvc2.errors.minlength && !cvc2.errors.maxlength && !cvc2.errors.pattern">
CVC must be 3 numbers.
</span>
</md-hint>
</md-input-container>
...
<button type="submit" md-raised-button color="primary" (click)="confirm($event, paymentCardForm.value)" [disabled]="isBusy || !paymentCardForm.valid">Confirm</button>
</form>
Without make validation patterns, You can easily trim begin and end spaces using these modules.Try this.
https://www.npmjs.com/package/ngx-trim-directive https://www.npmjs.com/package/ng2-trim-directive
Thank you.
