Awesome
<h1 align="center"> <img width="40" valign="bottom" src="https://angular.io/assets/images/logos/angular/angular.svg"> ngx-errors </h1> <h4 align="center">A declarative validation errors module for reactive forms.</h4><a href="https://ultimateangular.com" target="_blank"><img src="https://ultimateangular.com/assets/img/banners/ua-github.svg"></a>
<div align="center" markdown="1"> <a href="#installation">Installation</a> | <a href="#setup">Setup</a> | <a href="#documentation">Documentation</a> | <a href="http://plnkr.co/edit/JS0jSnelnLY9IbzFySfl?p=preview">Live demo</a> </div>
Overview
Why use ngx-errors, how to install and use.
What is it?
Declarative validation error messages for reactive forms.
Typically you'd do something like this:
<!-- without ngxErrors -->
<input type="text" formControlName="foo">
<div *ngIf="form.get('foo').hasError('required') && form.get('foo').touched">
Field is required
</div>
<div *ngIf="form.get('foo').hasError('minlength') && form.get('foo').dirty">
Min length is 5
</div>
With ngxErrors, we've taken a simple declarative approach that cleans up your templates to make validation easier:
<!-- with ngxErrors -->
<input type="text" formControlName="foo">
<div ngxErrors="foo">
<div ngxError="required" when="touched">
Field is required
</div>
<div ngxError="minlength" when="dirty">
Min length is 5
</div>
</div>
Check out the documentation below for all the syntax we provide.
Installation
yarn add @ultimate/ngxerrors
# OR
npm i @ultimate/ngxerrors
Setup
Just add ngx-errors to your module:
import { NgxErrorsModule } from '@ultimate/ngxerrors';
@NgModule({ imports: [ NgxErrorsModule ] })
Documentation
ngxErrors
The ngxErrors
directive works by dynamically fetching your FormControl under-the-hood, so simply take your formControlName
value and pass it into ngxErrors
:
<input type="text" formControlName="username">
<div ngxErrors="username">
// ...
</div>
This needs to be on a parent container that will encapsulate child ngxError
directives.
ngxError
The ngxError
directive takes either a string
or array
as arguments. The argument you pass in corresponds to any active errors exposed on your control, such as "required" or "minlength":
<input type="text" formControlName="username">
<div ngxErrors="username">
<div ngxError="minlength">
Min length is 5
</div>
</div>
Note: when using array syntax,
[]
bindings are needed
Using the array syntax, when any condition in the array is true the error will be shown:
<input type="text" formControlName="username">
<div ngxErrors="username">
<div [ngxError]="['minlength', 'maxlength']">
Min length is 5, max length is 10
</div>
</div>
ngxError #when
The when
directive takes either a string
or array
as arguments. It allows you to specify when you wish to display the error based on the control state, such as "dirty" or "touched":
<input type="text" formControlName="username">
<div ngxErrors="username">
<div ngxError="minlength" when="dirty">
Min length is 5
</div>
</div>
It also comes in array format for multiple rules:
<input type="text" formControlName="username">
<div ngxErrors="username">
<div ngxError="minlength" [when]="['dirty', 'touched']">
Min length is 5
</div>
</div>
Dynamic errors
You can optionally data-bind and dynamically create validation errors with ngxErrors:
<input type="text" formControlName="username">
<div ngxErrors="person.username">
<div *ngFor="let error of errors" [ngxError]="error.name" [when]="error.rules">
{{ error.text }}
</div>
</div>
With corresponding component class:
@Component({...})
export class MyComponent {
errors = [
{ name: 'required', text: 'This field is required', rules: ['touched', 'dirty'] },
{ name: 'minlength', text: 'Min length is 5', rules: ['dirty'] }
];
}
Nested FormGroup support
ngxErrors also supports FormGroups with control names using dot notation:
<div formGroupName="person">
<input type="text" formControlName="username">
<div ngxErrors="person.username">
<div ngxError="minlength" [when]="['dirty', 'touched']">
Min length is 5
</div>
</div>
</div>
Exported Directive API
ngx-errors exports itself as ngxErrors
, which means you can access information about your control error states elsewhere in your template using a template reference, such as #foo
.
Basic usage:
<div ngxErrors="username" #myError="ngxErrors"></div>
getError(name: string): any;
The getError
method returns the object associated with your error. This can be useful for dynamically displaying error rules.
Example: Adds
Min length is 5
when value is less than 5 characters (based onValidators.minLength(5)
).
<input type="text" formControlName="username">
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="minlength" when="dirty">
Min length should be {{ myError.getError('minlength')?.requiredLength }}
</div>
</div>
The error returned is identical to Angular's FormControl API
hasError(name: string, conditions?: string | string[]): boolean;
The hasError
method informs you if your control has the given error. This can be useful for styling elsewhere in your template based off the control's error state.
Example: Adds
class="required"
when "myError" has therequired
error.
<div [class.required]="myError.hasError('required')">
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
You can optionally pass in conditions in which to activate the error.
Example: Adds
class="required"
when "myError" has therequired
error and the states are'dirty'
and'touched'
.
<div [class.required]="myError.hasError('required', ['dirty', 'touched'])">
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
You can also use the "catch-all" selector to get the state of your entire control's validity, alongside on an optional state collection.
<div>
<div [ngClass]="{
invalid: myError.hasError('*'),
invalidTouchedDirty: myError.hasError('*', ['touched', 'dirty'])
}">
</div>
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
isValid(name: string, conditions?: string | string[]): boolean;
The isValid
method informs you if a your control is valid, or a property is valid. This can be useful for styling elsewhere in your template based off the control's validity state.
Example: Adds
class="valid"
when "myError" has norequired
error.
<div [class.valid]="myError.isValid('required')">
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
You can optionally pass in conditions in which to evaluate alongside the property you're checking is valid.
Example: Adds
class="valid"
when "myError" has norequired
error and the states are'dirty'
and'touched'
.
<div [class.valid]="myError.isValid('required', ['dirty', 'touched'])">
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
You can also use the "catch-all" selector to check if the control is valid, with no specific error properties, alongside on an optional state collection.
<div>
<div [ngClass]="{
valid: myError.isValid('*'),
validTouchedDirty: myError.isValid('*', ['touched', 'dirty'])
}">
</div>
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
</div>
hasErrors: boolean;
The hasErrors
property returns true
if your control has any number of errors. This can be useful for styling elsewhere in your template on a global control level rather than individual errors.
Example: Adds
class="errors"
when "myError" has any errors.
<div [class.errors]="myError.hasErrors">
<input type="text" formControlName="username">
</div>
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="required" when="dirty">
Field is required
</div>
<div ngxError="minlength" when="dirty">
Min length is 5
</div>
</div>
errors: { [key: string]: any; };
The errors
property returns the object associated with any active errors. This can be used to access any error properties on your control.
Example: Adds
Max length is 10, you typed (n)
when value is more than 10 characters (based onValidators.maxLength(10)
).
<input type="text" formControlName="username">
<div ngxErrors="username" #myError="ngxErrors">
<div ngxError="minlength" when="dirty">...</div>
<div ngxError="maxlength" when="dirty">...</div>
</div>
<div *ngIf="myError.errors?.maxlength">
Max length is 10, you typed {{ myError.errors.maxlength.actualLength }}
</div>
The errors returned are identical to Angular's FormControl API
Contributing
Please see the contributing guidelines.