namespace BlazorDemoApp.Models;

public record Product
{
    public int Id { get; set; }
    public required string Title { get; set; }
    public required string Description { get; set; }
    public decimal Price { get; set; }

    public List<int> Related { get; set; } = new();
}

using BlazorDemoApp.Models;

namespace BlazorDemoApp.Services;

public interface IProductStore
{
    IList<Product> GetAllProducts();
    Product GetProduct(int id);
    IList<Product> GetRelatedProducts(int productId);
}

public class ProductStore : IProductStore
{
    private static readonly List<Product> ProductsDataSource =
        new()
        {
            new Product
            {
                Id = 1, Title = "Smart speaker", Price = 22m,
                Description =
                    "This smart speaker delivers excellent sound quality and comes with built-in voice control, offering an impressive music listening experience.",
                Related = new List<int> { 2, 3 },
            },
            new Product
            {
                Id = 2, Title = "Regular speaker", Price = 89m,
                Description =
                    "Enjoy room-filling sound with this regular speaker. With its slick design, it perfectly fits into any room in your house.",
                Related = new List<int> { 1, 3 },
            },
            new Product
            {
                Id = 3, Title = "Speaker cable", Price = 12m,
                Description =
                    "This high-quality speaker cable ensures a reliable and clear audio connection for your sound system.",
            },
        };

    public IList<Product> GetAllProducts() => ProductsDataSource;

    public Product GetProduct(int id) => ProductsDataSource.Single(p => p.Id == id);

    public IList<Product> GetRelatedProducts(int productId)
    {
        var product = ProductsDataSource.Single(x => x.Id == productId);
        return ProductsDataSource.Where(p => product.Related.Contains(p.Id)).ToList();
    }
}

builder.Services.AddScoped<IProductStore, ProductStore>();

@page "/Products"
@using BlazorDemoApp.Models
@using BlazorDemoApp.Services

@inject IProductStore Store

@attribute [StreamRendering]

<h3>Products</h3>

@if (_products == null)
{
    <p>Loading...</p>
}
else
{
    @foreach (var item in _products)
    {
        <a href="/ProductDetails/@item.Id">
            <div>
                <div>
                    <h5>@item.Title</h5>
                </div>
                <div>
                    <h5>@item.Price.ToString("c")</h5>
                </div>
            </div>
        </a>
    }
}

@code {
    private IList<Product>? _products;

    protected override Task OnInitializedAsync() => GetProductsAsync();

    private async Task GetProductsAsync()
    {
        await Task.Delay(1000); // Simulates asynchronous loading to demonstrate streaming rendering
        _products = Store.GetAllProducts();
    }

}

@page "/ProductDetails/{ProductId}"
@using BlazorDemoApp.Models
@using BlazorDemoApp.Services

@inject IProductStore Store

@attribute [StreamRendering]

@if (_product == null)
{
    <p>Loading...</p>
}
else
{
    <div>
        <div>
            <h5>
                @_product.Title (@_product.Price.ToString("C"))
            </h5>
            <p>
                @_product.Description
            </p>
        </div>
        @if (_product.Related.Count > 0)
        {
            <div>
                <RelatedProducts ProductId="Convert.ToInt32(ProductId)" />
            </div>
        }
    </div>
    <NavLink href="/Products">Back</NavLink>
}

@code {
    private Product? _product;

    [Parameter]
    public string? ProductId { get; set; }

    protected override Task OnInitializedAsync() => GetProductAsync();

    private async Task GetProductAsync()
    {
        await Task.Delay(1000); // Simulates asynchronous loading to demonstrate streaming rendering
        _product = Store.GetProduct(Convert.ToInt32(ProductId));
    }

}

<RelatedProducts ProductId="Convert.ToInt32(ProductId)" />

@using BlazorDemoApp.Models
@using BlazorDemoApp.Services
@inject IProductStore Store

<button @onclick="LoadRelatedProducts">Related products</button>

@if (_loadRelatedProducts)
{
    @if (_relatedProducts == null)
    {
        <p>Loading...</p>
    }
    else
    {
        <div>
            @foreach (var item in _relatedProducts)
            {
                <a href="/ProductDetails/@item.Id">
                    <div>
                        <h5>@item.Title (@item.Price.ToString("C"))</h5>
                    </div>
                </a>
            }
        </div>
    }
}

@code{

    private IList<Product>? _relatedProducts;
    private bool _loadRelatedProducts;

    [Parameter]
    public int ProductId { get; set; }

    private async Task LoadRelatedProducts()
    {
        _loadRelatedProducts = true;
        await Task.Delay(1000); // Simulates asynchronous loading to demonstrate InteractiveServer mode
        _relatedProducts = Store.GetRelatedProducts(ProductId);
    }

}

<RelatedProducts ProductId="Convert.ToInt32(ProductId)" @rendermode="@InteractiveServer"/>

<script src="_framework/blazor.web.js"></script>

<RelatedProducts ProductId="Convert.ToInt32(ProductId)" @rendermode="@(new InteractiveServerRenderMode(false))"/>

@using static Microsoft.AspNetCore.Components.Web.RenderMode

public static class RenderMode
  {
    public static InteractiveServerRenderMode InteractiveServer { get; } = new InteractiveServerRenderMode();

    public static InteractiveWebAssemblyRenderMode InteractiveWebAssembly { get; } = new InteractiveWebAssemblyRenderMode();

    public static InteractiveAutoRenderMode InteractiveAuto { get; } = new InteractiveAutoRenderMode();
  }


public class InteractiveServerRenderMode : IComponentRenderMode
  {
    public InteractiveServerRenderMode()
      : this(true)
    {
    }

    public InteractiveServerRenderMode(bool prerender) => this.Prerender = prerender;

    public bool Prerender { get; }
  }

npx create-react-app tssample --template typescript

import React from "react";

export const Head = () => {
  return (
    <div>
      <h1>Hello</h1>
    </div>
  );
};

import { Head } from "./components/Head";
// ...

function App() {
  return (
    <div className="App">
      <Head />
      // ... 
    </div>
  );
}

export default App;

import React from "react";

export const Head = ({ title, isActive }) => {
  return (
    <div>
      <h1>{title}</h1>
      {isActive && <h3>Active</h3>}
    </div>
  );
};

{ 
    "compilerOptions": { 
        "strict": true  /* Enable all strict type-checking options. */ 
    } 
}

{ 
    "compilerOptions": { 
        "strict": true, 
        "noImplicitAny": false 
    } 
}

export const Head = ({ title, isActive }: Props) => {

Head.propTypes = {
  title: PropTypes.string,
  isActive: PropTypes.bool
}

<Head title="Hello" isActive={true} />

 <!-- Required for routing -->
<script src="~/node_modules/angular2/bundles/router.dev.js"></script>

 <!DOCTYPE html>
<html>
<head>
    <base href="/">

//same as before ...
import { ROUTER_PROVIDERS } from 'angular2/router';
 
//same as before ... 

@Component({
//same as before …
    providers: [
        ProductService,
        HTTP_PROVIDERS,
        ROUTER_PROVIDERS
    ]
})
//same as before ...

<div class='panel panel-primary'>
    <div class='panel-heading'>
        {{pageTitle}}
    </div>
</div>

import { Component } from 'angular2/core';

@Component({
    templateUrl: 'app/products/product-detail.component.html'
})
export class ProductDetailComponent  {
    pageTitle: string = 'Product Detail'; 
}

 { path: '/products', name: 'Products', component: ProductListComponent },

//same as before …
import { ROUTER_PROVIDERS, RouteConfig } from 'angular2/router';
 
//same as before …
 
@Component({
    //same as before …
})
@RouteConfig([
    { path: '/welcome', name: 'Welcome', component: WelcomeComponent, useAsDefault: true },
    { path: '/products', name: 'Products', component: ProductListComponent }
])
export class AppComponent {
    pageTitle: string = "DNT AngularJS 2.0 APP";
}

import { Component } from 'angular2/core';
 
@Component({
    templateUrl: 'app/home/welcome.component.html'
})
export class WelcomeComponent {
    public pageTitle: string = "Welcome";
}

<div class="panel panel-primary">
    <div class="panel-heading">
        {{pageTitle}}
    </div>
    <div class="panel-body">
        <h3 class="text-center">Default page</h3>
    </div>
</div>

 import { WelcomeComponent } from './home/welcome.component';

@Component({
    //same as before …
    template: `
     <div>
        <nav class='navbar navbar-default'>
            <div class='container-fluid'>
                <a class='navbar-brand'>{{pageTitle}}</a>
                <ul class='nav navbar-nav'>
                    <li><a [routerLink]="['Welcome']">Home</a></li>
                    <li><a [routerLink]="['Products']">Product List</a></li>
                </ul>
            </div>
        </nav>
        <div class='container'>
            <router-outlet></router-outlet>
        </div>
     </div>
    `,
    //same as before …
})

 import { ROUTER_PROVIDERS, RouteConfig, ROUTER_DIRECTIVES } from 'angular2/router';

 directives: [ROUTER_DIRECTIVES],

//same as before …

import { ProductDetailComponent } from './products/product-detail.component';
 
@Component({
    //same as before …
})
@RouteConfig([
    //same as before …
    { path: '/product/:id', name: 'ProductDetail', component: ProductDetailComponent }
])
//same as before …

 <td>{{ product.productName }}</td>

<td>
    <a [routerLink]="['ProductDetail', {id: product.productId}]">
        {{product.productName}}
    </a>
</td>

import { Component, OnInit } from 'angular2/core';
import { ROUTER_DIRECTIVES } from 'angular2/router';
//same as before …
 
@Component({
    //same as before …
    directives: [StarComponent, ROUTER_DIRECTIVES]
})

import { Component } from 'angular2/core';
import { RouteParams } from 'angular2/router';
 
@Component({
    templateUrl: 'app/products/product-detail.component.html'
})
export class ProductDetailComponent {
    pageTitle: string = 'Product Detail';
 
    constructor(private _routeParams: RouteParams) {
        let id = +this._routeParams.get('id');
        this.pageTitle += `: ${id}`;
    } 
}

<div class='panel panel-primary'>
    <div class='panel-heading'>
        {{pageTitle}}
    </div>
    <div class='panel-footer'>
        <a class='btn btn-default' (click)='onBack()' style='width:80px'>
            <i class='glyphicon glyphicon-chevron-left'></i> Back
        </a>
    </div>    
</div>

import { Component } from 'angular2/core';
import { RouteParams, Router } from 'angular2/router';
 
@Component({
    templateUrl: 'app/products/product-detail.component.html'
})
export class ProductDetailComponent {
    pageTitle: string = 'Product Detail';
 
    constructor(private _routeParams: RouteParams, private _router: Router) {
        let id = +this._routeParams.get('id');
        this.pageTitle += `: ${id}`;
    }
 
    onBack(): void {
        this._router.navigate(['Products']);
    }
}

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
 
        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
            constraints: new { controller = "Home" } // for catch all to work, Home|About|SomeName
        );
 
        // Route override to work with Angularjs and HTML5 routing
        routes.MapRoute(
            name: "NotFound",
            url: "{*catchall}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
        );
    }
}

• زیرا نیاز به build processهایی داریم که به ما امکان استفاده از ES6, SCSS و دیگر ویژگیهای عالی را خواهند داد.
  
• جهت ساخت و یکی‌سازی فایل‌های تمپلیت
  
• بارگذاری نکردن تمامی فایل‌ها به صورت یکجا در زمان Startup 
  
• می‌توانیم تسک‌هایی از قبیل Server-side rendering, code-splitting را انجام دهیم.
  

 >ng g m CustomValidators -m app.module --routing

 >ng g c CustomValidators/user-register

 >ng g cl CustomValidators/user

export class User {
  constructor(
    public username: string = "",
    public email: string = "", 
    public password: string = "", 
    public confirmPassword: string = "" 
  ) {}
}

 >ng g d CustomValidators/EmailValidator -m custom-validators.module

import { Directive } from "@angular/core";
import { AbstractControl, NG_VALIDATORS, Validator } from "@angular/forms";

@Directive({
  selector:
    "[appEmailValidator][formControlName],[appEmailValidator][formControl],[appEmailValidator][ngModel]",
  providers: [
    {
      provide: NG_VALIDATORS,
      useExisting: EmailValidatorDirective,
      multi: true
    }
  ]
})
export class EmailValidatorDirective implements Validator {
  validate(element: AbstractControl): { [key: string]: any } {
    const emailRegex = /\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
    const valid = emailRegex.test(element.value);
    return valid ? null : { appEmailValidator: true };
  }
}

<input #email="ngModel" required appEmailValidator type="text" class="form-control" 
name="email" [(ngModel)]="model.email">

selector:
"[appEmailValidator][formControlName],[appEmailValidator][formControl],[appEmailValidator][ngModel]",

"apps": [
{
   // ...
   "prefix": "app",

 selector: "[appEmailValidator]"

  providers: [
    {
      provide: NG_VALIDATORS,
      useExisting: EmailValidatorDirective,
      multi: true
    }

 export class EmailValidatorDirective implements Validator {

 validate(element: AbstractControl): { [key: string]: any }

validate(element: AbstractControl): { [key: string]: any } {
  const emailRegex = /\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
  const valid = emailRegex.test(element.value);
  return valid ? null : { appEmailValidator: true };
}

<input #email="ngModel" required appEmailValidator type="text" class="form-control"
name="email" [(ngModel)]="model.email">

 { required:true }

{ minlength : {
     requiredLength : 3,
     actualLength : 1
   }
}

 { appEmailValidator: true }

<div class="alert alert-danger"  *ngIf="email.errors.appEmailValidator">
The entered email is not valid.
</div>

public password: string = "",
public confirmPassword: string = ""

 >ng g d CustomValidators/EqualValidator -m custom-validators.module

import { Directive, Attribute } from "@angular/core";
import { Validator, AbstractControl, NG_VALIDATORS } from "@angular/forms";

@Directive({
  selector:
    "[appValidateEqual][formControlName],[appValidateEqual][formControl],[appValidateEqual][ngModel]",
  providers: [
    {
      provide: NG_VALIDATORS,
      useExisting: EqualValidatorDirective,
      multi: true
    }
  ]
})
export class EqualValidatorDirective implements Validator {
  constructor(@Attribute("compare-to") public compareToControl: string) {}

  validate(element: AbstractControl): { [key: string]: any } {
    const selfValue = element.value;
    const otherControl = element.root.get(this.compareToControl);

    console.log("EqualValidatorDirective", {
       thisControlValue: selfValue,
       otherControlValue: otherControl ? otherControl.value : null
    });

    if (otherControl && selfValue !== otherControl.value) {
      return {
        appValidateEqual: true // Or a string such as 'Password mismatch.' or an abject.
      };
    }

    if (
      otherControl &&
      otherControl.errors &&
      selfValue === otherControl.value
    ) {
      delete otherControl.errors["appValidateEqual"];
      if (!Object.keys(otherControl.errors).length) {
        otherControl.setErrors(null);
      }
    }

    return null;
  }
}

export class EqualValidatorDirective implements Validator {
  constructor(@Attribute("compare-to") public compareToControl: string) {}

<input #password="ngModel" required type="password" class="form-control"
appValidateEqual compare-to="confirmPassword" name="password" [(ngModel)]="model.password">

export class EqualValidatorDirective implements Validator {
  constructor(@Attribute("compare-to") public compareToControl: string) {}

  validate(element: AbstractControl): { [key: string]: any } {
    const selfValue = element.value;
    const otherControl = element.root.get(this.compareToControl);

    console.log("EqualValidatorDirective", {
       thisControlValue: selfValue,
       otherControlValue: otherControl ? otherControl.value : null
    });

    if (otherControl && selfValue !== otherControl.value) {
      return {
        appValidateEqual: true // Or a string such as 'Password mismatch.' or an abject.
      };
    }

    if (otherControl && otherControl.errors && selfValue === otherControl.value) {
      delete otherControl.errors["appValidateEqual"];
      if (!Object.keys(otherControl.errors).length) {
        otherControl.setErrors(null);
      }
    }

    return null;

import { NgForm } from "@angular/forms";
import { User } from "./../user";
import { Component, OnInit } from "@angular/core";

@Component({
  selector: "app-user-register",
  templateUrl: "./user-register.component.html",
  styleUrls: ["./user-register.component.css"]
})
export class UserRegisterComponent implements OnInit {
  model = new User();

  constructor() {}

  ngOnInit() {}

  submitForm(form: NgForm) {
    console.log(this.model);
    console.log(form.value);
  }
}

<div class="container">
  <h3>Registration Form</h3>
  <form #form="ngForm" (submit)="submitForm(form)" novalidate>

    <div class="form-group" [class.has-error]="username.invalid && username.touched">
      <label class="control-label">User Name</label>
      <input #username="ngModel" required maxlength="8" minlength="4" type="text"
        class="form-control" name="username" [(ngModel)]="model.username">
      <div *ngIf="username.invalid && username.touched">
        <div class="alert alert-info">
          errors: {{ username.errors | json }}
        </div>
        <div class="alert alert-danger"  *ngIf="username.errors.required">
          username is required.
        </div>
        <div class="alert alert-danger"  *ngIf="username.errors.minlength">
          username should be minimum {{username.errors.minlength.requiredLength}} characters.
        </div>
        <div class="alert alert-danger"  *ngIf="username.errors.maxlength">
          username should be max {{username.errors.maxlength.requiredLength}} characters.
        </div>
      </div>
    </div>

    <div class="form-group" [class.has-error]="email.invalid && email.touched">
      <label class="control-label">Email</label>
      <input #email="ngModel" required appEmailValidator type="text" class="form-control"
        name="email" [(ngModel)]="model.email">
      <div *ngIf="email.invalid && email.touched">
        <div class="alert alert-info">
          errors: {{ email.errors | json }}
        </div>
        <div class="alert alert-danger"  *ngIf="email.errors.required">
          email is required.
        </div>
        <div class="alert alert-danger"  *ngIf="email.errors.appEmailValidator">
          The entered email is not valid.
        </div>
      </div>
    </div>

    <div class="form-group" [class.has-error]="password.invalid && password.touched">
      <label class="control-label">Password</label>
      <input #password="ngModel" required type="password" class="form-control"
        appValidateEqual compare-to="confirmPassword" name="password" [(ngModel)]="model.password">
      <div *ngIf="password.invalid && password.touched">
        <div class="alert alert-info">
          errors: {{ password.errors | json }}
        </div>
        <div class="alert alert-danger"  *ngIf="password.errors.required">
          password is required.
        </div>
        <div class="alert alert-danger"  *ngIf="password.errors.appValidateEqual">
          Password mismatch. Please complete the confirmPassword .
        </div>
      </div>
    </div>

    <div class="form-group" [class.has-error]="confirmPassword.invalid && confirmPassword.touched">
      <label class="control-label">Retype password</label>
      <input #confirmPassword="ngModel" required type="password" class="form-control"
        appValidateEqual compare-to="password" name="confirmPassword" [(ngModel)]="model.confirmPassword">
      <div *ngIf="confirmPassword.invalid && confirmPassword.touched">
        <div class="alert alert-info">
          errors: {{ confirmPassword.errors | json }}
        </div>
        <div class="alert alert-danger"  *ngIf="confirmPassword.errors.required">
          confirmPassword is required.
        </div>
        <div class="alert alert-danger"  *ngIf="confirmPassword.errors.appValidateEqual">
          Password mismatch.
        </div>
      </div>
    </div>

    <button class="btn btn-primary" [disabled]="form.invalid" type="submit">Ok</button>
  </form>
</div>

>npm install
>ng build --watch

>dotnet restore
>dotnet watch run

dotnet new blazor --interactivity Server

dotnet new blazor --interactivity WebAssembly

// ...

builder.Services.AddRazorComponents()
       .AddInteractiveServerComponents();

// ...

app.MapRazorComponents<App>()
   .AddInteractiveServerRenderMode();

// ...

builder.Services.AddRazorComponents()
    .AddInteractiveWebAssemblyComponents();

// ...

app.MapRazorComponents<App>()
    .AddInteractiveWebAssemblyRenderMode()
    .AddAdditionalAssemblies(typeof(Counter).Assembly);

<Project Sdk="Microsoft.NET.Sdk.BlazorWebAssembly">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <ProjectReference Include="..\BlazorDemoApp.Shared\BlazorDemoApp.Shared.csproj" />
  </ItemGroup>

</Project>

builder.Services.AddScoped<IProductStore, ProductStore>();

@using static Microsoft.AspNetCore.Components.Web.RenderMode
// ...
@using BlazorDemoApp.Client.Components.Store
@using BlazorDemoApp.Client.Components

<RelatedProducts ProductId="ProductId" @rendermode="@InteractiveWebAssembly"/>

using BlazorDemoApp.Services;
using Microsoft.AspNetCore.Mvc;

namespace BlazorDemoApp.Controllers;

[ApiController]
[Route("/api/[controller]")]
public class ProductsController : ControllerBase
{
    private readonly IProductStore _store;

    public ProductsController(IProductStore store) => _store = store;

    [HttpGet("[action]")]
    public IActionResult Related([FromQuery] int productId) => Ok(_store.GetRelatedProducts(productId));
}

builder.Services.AddControllers();
// ...
app.MapControllers();

@using BlazorDemoApp.Shared.Models
@inject HttpClient Http

<button class="btn btn-outline-secondary" @onclick="LoadRelatedProducts">Related products</button>

@if (_loadRelatedProducts)
{
    @if (_relatedProducts == null)
    {
        <p>Loading...</p>
    }
    else
    {
        <div class="mt-3">
            @foreach (var item in _relatedProducts)
            {
                <a href="/ProductDetails/@item.Id">
                    <div class="col-sm">
                        <h5 class="mt-0">@item.Title (@item.Price.ToString("C"))</h5>
                    </div>
                </a>
            }
        </div>
    }
}

@code{

    private IList<Product>? _relatedProducts;
    private bool _loadRelatedProducts;

    [Parameter]
    public int ProductId { get; set; }

    private async Task LoadRelatedProducts()
    {
        _loadRelatedProducts = true;
        var uri = $"/api/products/related?productId={ProductId}";
        _relatedProducts = await Http.GetFromJsonAsync<IList<Product>>(uri);
    }

}

System.InvalidOperationException: Cannot provide a value for property 'Http' on type 'RelatedProducts'.
There is no registered service of type 'System.Net.Http.HttpClient'.

<RelatedProducts ProductId="ProductId" @rendermode="@InteractiveWebAssembly"/>

builder.Services.AddScoped(sp => new HttpClient 
{ 
    BaseAddress = new Uri("http://localhost/") 
});

using BlazorDemoApp.Shared.Models;

namespace BlazorDemoApp.Shared.Data;

public interface IProductStore
{
    IList<Product> GetAllProducts();
    Product GetProduct(int id);
    Task<IList<Product>?> GetRelatedProducts(int productId);
}

public Task<IList<Product>?> GetRelatedProducts(int productId)
    {
        var product = ProductsDataSource.Single(x => x.Id == productId);
        return Task.FromResult<IList<Product>?>(ProductsDataSource.Where(p => product.Related.Contains(p.Id))
                                                                 .ToList());
    }

[HttpGet("[action]")]
public async Task<IActionResult> Related([FromQuery] int productId) =>
        Ok(await _store.GetRelatedProducts(productId));

public class ClientProductStore : IProductStore
{
    private readonly HttpClient _httpClient;

    public ClientProductStore(HttpClient httpClient) => _httpClient = httpClient;

    public IList<Product> GetAllProducts() => throw new NotImplementedException();

    public Product GetProduct(int id) => throw new NotImplementedException();

    public Task<IList<Product>?> GetRelatedProducts(int productId) =>
        _httpClient.GetFromJsonAsync<IList<Product>>($"/api/products/related?productId={productId}");
}

builder.Services.AddScoped<IProductStore, ClientProductStore>();
builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });

@inject IProductStore ProductStore

private async Task LoadRelatedProducts()
{
   _loadRelatedProducts = true;
   _relatedProducts = await ProductStore.GetRelatedProducts(ProductId);
}

import React, { Component } from "react";

class Form extends Component {
    state = {
        data:{},
        errors:{}
     }

import Joi from "@hapi/joi";

  doSubmit = () => {
    // call the server
    console.log("Submitted!");
  };

import Form from "./common/form";
// ...

class LoginForm extends Form {

  renderButton(label) {
    return (
      <button disabled={this.validate()} className="btn btn-primary">
        {label}
      </button>
    );
  }

{this.renderButton("Login")}

  import Input from "./input";
  //...

  renderInput(name, label) {
    const { data, errors } = this.state;
    return (
      <Input
        name={name}
        label={label}
        value={data[name]}
        onChange={this.handleChange}
        error={errors[name]}
      />
    );

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        {this.renderInput("username", "Username")}
        {this.renderInput("password", "Password")}
        {this.renderButton("Login")}
      </form>
    );
  }

  renderInput(name, label, type = "text") {
    const { data, errors } = this.state;
    return (
      <Input
        name={name}
        type={type}
        label={label}
        value={data[name]}
        onChange={this.handleChange}
        error={errors[name]}
      />
    );
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        {this.renderInput("username", "Username")}
        {this.renderInput("password", "Password", "password")}
        {this.renderButton("Login")}
      </form>
    );
}

import React from "react";

const Input = ({ name, type, label, value, error, onChange }) => {
  return (
    <div className="form-group">
      <label htmlFor={name}>{label}</label>
      <input
        value={value}
        onChange={onChange}
        id={name}
        name={name}
        type={type}
        className="form-control"
      />
      {error && <div className="alert alert-danger">{error}</div>}
    </div>
  );
};

export default Input;

<input
  value={value}
  name={name}
  type={type}
  onChange={onChange}
  id={name}
  className="form-control"
/>

import React from "react";

const Input = ({ name, label, error, ...rest }) => {
  return (
    <div className="form-group">
      <label htmlFor={name}>{label}</label>
      <input {...rest} name={name} id={name} className="form-control" />
      {error && <div className="alert alert-danger">{error}</div>}
    </div>
  );
};

export default Input;