ng-error-messages

A library that help you show error messages based in rules validation. Based in repository of my partner Arthur

• Demo
• Reason
• Installation
• Usage
• Validators
• Customizing
• Development
• TODO

Demo

https://ouracademy.github.io/error-messages/

Reason

Tired to always write this in your angular app:

<input type="text" formControlName="text">
 
<div *ngIf="form.get('text').hasError('required') && form.get('text').touched">
  Field is required
</div>
 

And repeat this to every field in every form in every view.

So you can instead do this:

                <input placeholder="Texto:"  formControlName="text">
                <div errorMessage="text" alias="Super Texto" ></div>
                

And it will do the same in very uniform way in all your fields in every forms in all your views. This package will create validation messages for you. It contains predefined validation messages.

Installation

Install the npm module by running:

npm install ng-error-messages --save

Usage

You can see the demo app to have a more detail of the usage.

1. Import the ErrorMessageModule:

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { HttpModule } from '@angular/http';
import { AppComponent }           from './app.component';
import { ErrorMessageModule } from 'ng-error-messages';
 
@NgModule({
  imports: [
    BrowserModule,
    HttpModule,
    ErrorMessageModule
  ],
  declarations: [ AppComponent ],
  bootstrap:    [ AppComponent ]
})
export class AppModule { }

2. Init the DisplayErrorService for your application:

import { Component } from '@angular/core';
import { FormGroup, FormBuilder, Validators } from '@angular/forms';
import { DisplayErrorService } from 'ng-error-messages'
 
@Component({
  selector: 'demo-app',
  templateUrl: 'index.component.html'
})
export class IndexComponent {
  form: FormGroup;
  valueFormated
  constructor(
    private displayErrorService: DisplayErrorService,
    private fb: FormBuilder) { }
 
  ngOnInit(): void {
    this.buildForm();
  }
 
 
  buildForm(): void {
    this.form = this.fb.group({
      'text': ['', [
        Validators.required,
        Validators.minLength(5),
        Validators.maxLength(10)
      ]]
    });
  }
  setLanguage(lang) {
    this.displayErrorService
      .setLanguage(lang)
      .subscribe(r => {
        console.log("change language")
      }, err => {
        alert(err)
      })
  }
}
 
 

3. Use it on your template:

    <div [formGroup]="form">
        <h2>
            Messager for errors
        </h2>
        <div>
                <input placeholder="Texto:"  formControlName="text">
                <div errorMessage="text" alias="Super Texto" ></div>
        </div>
    </div>
 

Validators

This is the list of the supported validations

angular built-in validators

• required
• minlength
• maxlength
• pattern
• min
• max
• email

Customizing

At this moment only support alias for every field. TODO: Customize messages for error type.

Development

Prepare your environment

• Install Node.js and NPM (should come with)
• Install local dev dependencies: npm install while current directory is this repo

Development server

Run npm start to start a development server on port 8000 with auto reload + tests.

Testing

Run npm test to run tests once or npm run test:watch to continually run tests.

Release

• Bump the version in package.json (once the module hits 1.0 this will become automatic)

npm run release

TODO

This package it's creating on free times after university...and theses... For now works with Reactive Driven Forms, it wasn't tested with Template Driven Forms. Probably it will work, if work send us a message.