Negatively Proportional Model

    TypeScript icon, indicating that this package has built-in type declarations

    12.2.2 • Public • Published


    This library was generated with Angular CLI version 12.2.0.

    For Angular 12.x.y => use @gpeel/my-validators 12.0.0 or more recent

    For Angular 11.x.y => use @gpeel/plog@11.2.1 (last version for angular 11)



    my validators npm install

        npm i @gpeel/my-validators

    my validators simplest example

    To have all included validator messages as :

    Validation error messages appear when the field is blurred or dirty. Thers is default debounce of 300ms (optionnaly changeable)


    Declare in your AppModule the MyValidatorsModule:

      declarations: [
      imports: [
        FormsModule, ReactiveFormsModule, BrowserModule,
        MyValidatorsModule, // <<< HERE
      bootstrap: [AppComponent]
    export class AppModule {

    In you app code

    Replace Angular Validators by MyValidators ie replace: // import {Validators} from '@angular/forms';

    with: // import {MyValidators} from '@gpeel/my-validators';

    BEFORE :

    this.form ={
      name: [this.originalName,

    AFTER :

    // import {MyValidators} from '@gpeel/my-validators';
    this.form ={
      name: [this.originalName,

    And then add myErrorMsg in the <input>

    <div class="form-group">
      <label for="name">Name</label>
      <input class="form-control" formControlName="name" id="name" myErrorMsg>

    The myErrorMsg Directive will create a component under <input> to show validation error messages.

    That's ALL !

    Of Course you can optionnaly place the error messages preceisely wher you want and customize the message with dedicated services. Look at the examples on github

    choosing when the error messages appear

    Buy default the errors are show when an <input> turns touched or dirty and has some errors to show.

    All error messages are shown (not only the first, except required which behaves as usual ie lonely).

    To override the function used to show error you can provide an alternative function with the followinf settings:

        // MY_SHOW_ERROR_MSG_FUNCTION_API enable to change to function used by <my-error-msg> component to show the errors
        // default value:
        // useValue: (control: AbstractControl) => (control.dirty || control.touched)
        // not showing error until blurred
      (control: AbstractControl) => control.touched

    You also have the option to change the strategy to show error function on a specific <input> with the param showErrorFunction:

    <input [showErrorFunction]="showFn" class="form-control" formControlName="name7" id="name7" myErrorMsg>
    showFn = (control: AbstractControl) => control.touched;

    This cutomization is available on the component <my-error-msg> if you prefer:

    <input [myErrorMsg]="name7Errors" class="form-control" formControlName="name7" id="name7">
    <my-error-msg #name7Errors="myErrorMsg" [showErrorFunction]="showFn"></my-error-msg>

    Strategy Validators / Error-Message

    This is a 2-steps process:

    1- the MyValidators will compute a "msg" property added to the control.error when invoked by Angular.

    Example for 2 validation errors with minLength and pattern validators:

    name.errors = {
      "minlength": {
        "requiredLength": 3,
        "actualLength": 2,
        "msg": "the length should be more than 3 characters"  // <<<< added by MyValidators
      "pattern": {
        "requiredPattern": "/titi/",
        "actualValue": "Th",
        "msg": "the field should respect the pattern /titi/ "  // <<<< added by MyValidators

    2- then the ui component extracts control.errors..msg for each key present in control.errors and show it HTML.

    Since those 2 steps are completely disctinct, you can code validators that elaborate this "msg" property as you want ( inside an Angular service, connected to a i18n framework to get translation ..etc). And on the other you can devise different UI components to show the errors in HTML.

    See more realistic and flexible examples on github :

    • reactive3-flexible-validators: this example provide a ValidatorService and a MessageService where you define the value of each validator error key.
    • reactive4-i18n-transloco: extending from the reactive3-flexible-validators example and connecting the MessageService to a translator tool @ngneat/transloco in this case.

    Plog install in your main project (OPTIONNAL)

    my-validators uses a simple logger @gpeel/plog to enable/disable the output logs of validators.

    More information on:

    If you want to activate those logs, in your main project do an explicit install:

        npm i @gpeel/plog

    And declare :

        PlogModule.forRoot(environment) // <<< HERE, takes into account you loggers definition in environment.ts


    Your ./environments/environments.ts and environments-prod.ts would typically look like :

    export const environment = {
      production: false,
      plog: {
        error: 'color:red',
        warn: 'color:orange',
        // info: 'color:blue',
        // debug: 'color:limegreen;font-weight:bold',

    DEV environment.ts

    And your developpment environment.ts would typically activate much more loggers (here all are activated) :

    You have specific loggers to have feedback when the @component <my-error-msg> recomputes its error messages and what is the value of control.errors for that <input>.

    • @REFRESH tells you each time the component is refreshed by Angular (on this picture, it is the 8th time the component has been refreshed)
    • @VALID gives the error messages that will be shown

    See below.

    export const environment = {
      production: false,
      plog: {
        debug: 'color:limegreen;font-weight:bold',
        info: 'color:blue',
        error: 'color:red',
        warn: 'color:orange',
        // Specific loggers for @gpeel/my-validators
        validationCompute: ['color:orange', '@VALID'], // tracing validators when they compute
        validationErrorMsgRefresh: ['color:orange', '@VALID_PERF'], // tracing refresh of <my-error-msg>
        validationErrorMsgCreation: ['color:orange', '@ERROR_MSG_NEW'], // tracing creation of component <my-error-msg>
        // NG hooks
        ngOnChanges: ['color:orange', 'OnChange'],
        ngOnInit: ['color:orange', 'OnInit'],
        ngOnDestroy: ['color:orange', 'OnDestroy'],
        ngDoCheck: ['color:orange', 'DoCheck'],
        ngAfterContentInit: ['color:orange', 'AfterContentInit'],
        ngAfterContentChecked: ['color:orange', 'AfterContentChecked'],
        ngAfterViewInit: ['color:orange', 'AfterViewInit'],
        ngAfterViewChecked: ['color:orange', 'AfterViewChecked'],
        // look at
        // or at
        // to have the complete list of loggers


    npm i @gpeel/my-validators

    DownloadsWeekly Downloads






    Unpacked Size

    789 kB

    Total Files


    Last publish


    • gpeel