在本章中,我们将讨论与Angular 4相关的一些示例.
首先,我们创建了一个示例,其中显示了输入为用户名的登录表单和密码.输入正确的值后,它将进入内部并显示另一个表格,您可以输入客户详细信息.此外,我们创建了四个组件 - 页眉,页脚,用户登录和主页.
使用以下命令创建组件 :
C:\ngexamples\aexamples>ng g component header installing component create src\app\header\header.component.css create src\app\header\header.component.html create src\app\header\header.component.spec.ts create src\app\header\header.component.ts update src\app\app.module.ts
C:\ngexamples\aexamples>ng g component footer installing component create src\app\footer\footer.component.css create src\app\footer\footer.component.html create src\app\footer\footer.component.spec.ts create src\app\footer\footer.component.ts update src\app\app.module.ts
C:\ngexamples\aexamples>ng g component userlogin installing component create src\app\userlogin\userlogin.component.css create src\app\userlogin\userlogin.component.html create src\app\userlogin\userlogin.component.spec.ts create src\app\userlogin\userlogin.component.ts update src\app\app.module.ts
C:\ngexamples\aexamples>ng g component mainpage installing component create src\app\mainpage\mainpage.component.css create src\app\mainpage\mainpage.component.html create src\app\mainpage\mainpage.component.spec.ts create src\app\mainpage\mainpage.component.ts update src\app\app.module.ts
在 app.module.ts 中,父模块在创建时添加了所有组件.该文件如下所示:<
import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { ReactiveFormsModule } from '@angular/forms'; import { RouterModule, Routes} froms '@angular/router'; import { BrowserAnimationsModule } from '@angular/platform-browser/animations'; import {MdTableModule} from '@angular/material'; import {HttpModule} from "@angular/http"; import {MdInputModule} from '@angular/material'; import { AppComponent } from './app.component'; import { HeaderComponent } from './header/header.component'; import { FooterComponent } from './footer/footer.component'; import { UserloginComponent } from './userlogin/userlogin.component'; import { MainpageComponent } from './mainpage/mainpage.component'; const appRoutes: Routes = [ { path: '', component: UserloginComponent }, { path: 'app-mainpage', component: MainpageComponent } ]; @NgModule({ declarations: [ AppComponent, HeaderComponent, FooterComponent, UserloginComponent, MainpageComponent ], imports: [ BrowserModule, ReactiveFormsModule, RouterModule.forRoot(appRoutes), BrowserAnimationsModule, HttpModule, MdTableModule, MdInputModule ], providers: [], bootstrap: [AppComponent] }) export class AppModule { }
上面创建的组件是加/减;
import { HeaderComponent } from './header/header.component'; import { FooterComponent } from './footer/footer.component'; import { UserloginComponent } from './userlogin/userlogin.component'; import { MainpageComponent } from './mainpage/mainpage.component';
组件在声明中加上 :
declarations: [ AppComponent, HeaderComponent, FooterComponent, UserloginComponent, MainpageComponent ],
在父 app.component.html 中,我们添加了用户可以看到的文件的主要结构.
<div class="mainpage"> <app-header></app-header> <router-outlet></router-outlet> <app-footer></app-footer> </div>
我们创建了一个div并添加了< app-header></app-header> ,<router-outlet></router-outlet> 和< app-footer></app-footer> .
< router-outlet></router-outlet> 用于在一个页面之间导航到另一个页面.这里的页面是登录表单,一旦成功,它将重定向到主页,即客户表单.
首先获取登录表单,然后获取主页面. component.html,更改在 app.module.ts 中完成,如下所示 :
import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { ReactiveFormsModule } from '@angular/forms'; import { RouterModule, Routes} from '@angular/router'; import { BrowserAnimationsModule } from '@angular/platform-browser/animations'; import {MdTableModule} from '@angular/material'; import {HttpModule} from "@angular/http"; import {MdInputModule} from '@angular/material'; import { AppComponent } from './app.component'; import { HeaderComponent } from './header/header.component'; import { FooterComponent } from './footer/footer.component'; import { UserloginComponent } from './userlogin/userlogin.component'; import { MainpageComponent } from './mainpage/mainpage.component'; const appRoutes: Routes = [ { path: '', component: UserloginComponent }, { path: 'app-mainpage', component: MainpageComponent } ]; @NgModule({ declarations: [ AppComponent, HeaderComponent, FooterComponent, UserloginComponent, MainpageComponent ], imports: [ BrowserModule, ReactiveFormsModule, RouterModule.forRoot(appRoutes), BrowserAnimationsModule, HttpModule, MdTableModule, MdInputModule ], providers: [], bootstrap: [AppComponent] }) export class AppModule { }
我们从 @ anuglar/router 导入了 RouterModule 和路由 .在导入中,RouterModules将appRoutes作为上面定义为&minus的param;
const appRoutes: Routes = [ { path: '', component: UserloginComponent }, { path: 'app-mainpage', component: MainpageComponent } ];
路由获取组件数组,默认情况下调用userloginComponent.
在 userlogin.component中.ts ,我们已导入路由器并根据条件导航到mainpage.component.html,如下所示 :
import { Component, OnInit } from '@angular/core'; import { FormGroup, FormControl, Validators} from '@angular/forms'; import { Router} from '@angular/router'; @Component({ selector: 'app-userlogin', templateUrl: './userlogin.component.html', styleUrls: ['./userlogin.component.css'] }) export class UserloginComponent implements OnInit { formdata; constructor(private router: Router) { } ngOnInit() { this.formdata = new FormGroup({ uname: new FormControl("", Validators.compose([ Validators.required, Validators.minLength(6) ])), passwd: new FormControl("", this.passwordvalidation) }); } passwordvalidation(formcontrol) { if (formcontrol.value.length < 5) { return {"passwd" : true}; } } onClickSubmit(data) { console.log(data.uname); if (data.uname=="systemadmin" && data.passwd=="admin123") { alert("Login Successful"); this.router.navigate(['app-mainpage']) } else { alert("Invalid Login"); return false; } } }
以下是 app.component.ts的.ts文件.其中只有默认的详细信息.
import { Component } from '@angular/core'; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.css'] }) export class AppComponent {title = 'app';}
现在让我们展示每个组件文件的详细信息.首先,我们将首先采用标头组件.对于新组件,将创建四个文件 header.component.ts,header.component.html,header.component.css和header.component.spec.ts .
import { Component, OnInit } from '@angular/core'; @Component({ selector: 'app-header', templateUrl: './header.component.html', styleUrls: ['./header.component.css'] }) export class HeaderComponent implements OnInit { constructor() { } ngOnInit() {} }
<div> <hr /> </div>
我们还没有添加任何CSS.这使得header.component.css文件为空.此外, header.compoent.spec.ts 文件为空,因为此处不考虑测试用例.
对于标题,我们将绘制一条水平线.可以添加徽标或任何其他细节,使标题看起来更具创意.
现在让我们考虑创建一个页脚组件.
页脚组件, footer.component.ts,footer.component.html,footer.component.spec.ts和footer.component.css 文件已创建.
import { Component, OnInit } from '@angular/core'; @Component({ selector: 'app-footer', templateUrl: './footer.component.html', styleUrls: ['./footer.component.css'] }) export class FooterComponent implements OnInit { constructor() { } ngOnInit() { } }
<hr/>
由于我们尚未添加任何css, footer.component.css 文件为空.此外, footer.compoent.spec.ts 文件为空,因为此处不考虑测试用例.
对于页脚,我们只绘制一个水平如.html文件中所示的行.
现在让我们看看userlogin组件的工作原理.创建的userlogin组件的以下文件是 userlogin.component.css,userlogin.component.html,userlogin.component.ts,和 userlogin.component.spec.ts.
文件的详细信息如下 :
<div class="form_container"> <form [formGroup]="formdata" (ngSubmit) = "onClickSubmit(formdata.value)" > <header>Login</header> <label>Username <span>*</span></label> <input type="text" name="uname" formControlName="uname"/> <div class="help">At least 6 character</div> <label>Password <span>*</span></label> <input type="password" class="fortextbox" name="passwd" formControlName="passwd"/> <div class="help">Use upper and lowercase lettes as well</div> <button [disabled]="!formdata.valid" value="Login">Login</button> </form> </div>
在这里,我们创建了带有两个输入控件的表单用户名和密码.这是一种模型驱动的表单方法,其细节在第14章 - 表单中进行了解释.
我们认为用户名和密码是强制性的,因此对其进行了验证. TS.单击提交按钮后,控件将传递到 onClickSubmit ,该文件在ts文件中定义.
import { Component, OnInit } from '@angular/core'; import { FormGroup, FormControl, Validators} from '@angular/forms'; import { Router} from '@angular/router'; @Component({ selector: 'app-userlogin', templateUrl: './userlogin.component.html', styleUrls: ['./userlogin.component.css'] }) export class UserloginComponent implements OnInit { formdata; constructor(private router: Router) { } ngOnInit() { this.formdata = new FormGroup({ uname: new FormControl("", Validators.compose([ Validators.required, Validators.minLength(6) ])), passwd: new FormControl("", this.passwordvalidation) }); } passwordvalidation(formcontrol) { if (formcontrol.value.length < 5) { return {"passwd" : true}; } } onClickSubmit(data) { console.log(data.uname); if (data.uname == "systemadmin" && data.passwd == "admin123") { alert("Login Successful"); this.router.navigate(['app-mainpage']) } } }
对于formcontrol和验证,模块导入如下所示
import { FormGroup, FormControl, Validators} from '@angular/forms';
当用户和密码正确时,我们需要路由器导航到其他组件.为此,路由器导入如下所示 :
import { Router} from '@angular/router';
在 ngOnInit 中,表单的验证完成.我们需要用户名超过六个字符,并且该字段是必填字段.同样的条件也适用于密码.
点击提交后,我们可以检查用户名是 systemadmin ,密码是 admin123 .如果是,则会出现一个对话框,显示登录成功,路由器将导航到app-mainpage,这是主页组件的选择器.
为 userlogin.component.css 文件中的表单添加了css :
.form_container{ margin : 0 auto; width:600px; } form { background: white; width: 500px; box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.7); font-family: lato; position: relative; color: #333; border-radius: 10px; } form header { background: #FF3838; padding: 30px 20px; color: white; font-size: 1.2em; font-weight: 600; border-radius: 10px 10px 0 0; } form label { margin-left: 20px; display: inline-block; margin-top: 30px; margin-bottom: 5px; position: relative; } form label span { color: #FF3838; font-size: 2em; position: absolute; left: 2.3em; top: -10px; } form input { display: block; width: 50%; margin-left: 20px; padding: 5px 20px; font-size: 1em; border-radius: 3px; outline: none; border: 1px solid #ccc; } form .help { margin-left: 20px; font-size: 0.8em; color: #777; } form button { position: relative; margin-top: 30px; margin-bottom: 30px; left: 50%; transform: translate(-50%, 0); font-family: inherit; color: white; background: #FF3838; outline: none; border: none; padding: 5px 15px; font-size: 1.3em; font-weight: 400; border-radius: 3px; box-shadow: 0px 0px 10px rgba(51, 51, 51, 0.4); cursor: pointer; transition: all 0.15s ease-in-out; } form button:hover { background: #ff5252; }
userlogin.component.spec.ts 文件为空,因为现在没有测试用例.
现在让我们讨论主页组件的工作原理.为主页组件创建的文件是 mainpage.component.ts,mainpage.component.html,mainpage.component.css,和 mainpage.component.spect.ts .
import { Component, OnInit, ViewChild} from '@angular/core'; import { FormGroup, FormControl, Validators} from '@angular/forms'; import {Http, Response, Headers, RequestOptions } from "@angular/http"; import 'rxjs/add/operator/map'; @Component({ selector: 'app-mainpage', templateUrl: './mainpage.component.html', styleUrls: ['./mainpage.component.css'] }) export class MainpageComponent implements OnInit { formdata; cutomerdata; constructor(private http: Http) { } stateCtrl: FormControl; ngOnInit() { this.formdata = new FormGroup({ fname: new FormControl("", Validators.compose([ Validators.required, Validators.minLength(3) ])), lname: new FormControl("", Validators.compose([ Validators.required, Validators.minLength(3) ])), address:new FormControl(""), phoneno:new FormControl("") }); } onClickSubmit(data) { document.getElementById("custtable").style.display=""; this.cutomerdata = []; for (var prop in data) { this.cutomerdata.push(data[prop]); } console.log(this.cutomerdata); } }
我们创建了一个包含名字,姓氏,地址和电话号码的客户表格.使用 ngOnInit 功能完成相同的验证.单击提交后,控件将进入函数 onClickSubmit .这里,用于显示输入细节的表格可见.
customerdata从json转换为数组,这样我们就可以在表格中使用相同的ngFor,这是在.html文件中完成,如下所示.
<div class="form_container"> <form [formGroup]="formdata" (ngSubmit) = "onClickSubmit(formdata.value)" > <header>Customer Details</header> <label>FirstName <span>*</span></label> <input type="text" name="fname" formControlName="fname"/> <label>LastName <span>*</span></label> <input type="text" name="lname" formControlName="lname"/> <label>Address <span></span></label> <input type="text" name="address" formControlName="address"/> <label>Phone No <span></span></label> <input type="text" name="phoneno" formControlName="phoneno"/> <button [disabled]="!formdata.valid" value="Submit">Submit</button> </form> </div> <br/> <div id="custtable" style="display:none;margin:0 auto;"> <table> <tr> <td>FirstName</td> <td>LastName</td> <td>Address</td> <td>Phone No</td> </tr> <tr> <td *ngFor="let data of cutomerdata"> <h5>{{data}}</h5> </td> </tr> </table> </div>
这里,第一个div有客户详细信息,第二个div有表格,这将显示输入的详细信息. userlogin和客户详细信息的显示如下所示.这是包含登录表单和页眉和页脚的页面.
输入详细信息后,显示如下所示
点击提交后,会出现一个对话框,显示登录成功.
如果细节无效,则会出现一个对话框,显示无效登录,如下所示 :
如果登录成功,它将进入下一个形式的客户详细信息,如下所示 :
输入详细信息后提交后,会出现一个对话框,显示客户详细信息已添加,如下面的屏幕截图所示 :
当我们在上面的屏幕截图中单击"确定"时,详细信息将显示如下面的屏幕截图所示 :