本篇文章给大家详细介绍一下angular中的模板语法。有一定的参考价值，有需要的朋友可以参考一下，希望对大家有所帮助。
相关教程推荐：《angular教程》
插值表达式
- test-interpolation.component.ts
@Component({
selector: 'app-test-interpolation',
templateUrl: './test-interpolation.component.html',
styleUrls: ['./test-interpolation.component.css']
})
export class TestInterpolationComponent implements OnInit {
title = '插值表达式';
constructor() { }
ngOnInit() {
}
getValue(): string {
return '值';
}
}- test-interpolation.component.html
<div class="panel panel-primary">
<div class="panel-heading">基插值语法</div>
<div class="panel-body">
<h3>
欢迎来到 {{title}}！
</h3>
<h3>2+2 = {{2 + 2}}</h3>
<h3>调用方法{{getValue()}}</h3>
</div>
</div>模板变量
- test-template-variables.component.ts
@Component({
selector: 'app-test-template-variables',
templateUrl: './test-template-variables.component.html',
styleUrls: ['./test-template-variables.component.css']
})
export class TestTempRefVarComponent implements OnInit {
constructor() { }
ngOnInit() {
}
public saveValue(value: string): void {
console.log(value);
}
}- test-template-variables.component.html
<div class="panel panel-primary">
<div class="panel-heading">模板变量</div>
<div class="panel-body">
<input #templateInput>
<p>{{templateInput.value}}</p>
<button class="btn btn-success" (click)="saveValue(templateInput.value)">局部变量</button>
</div>
</div>值绑定、事件绑定、双向绑定
值绑定：[]
- test-value-bind.component.ts
@Component({
selector: 'app-test-value-bind',
templateUrl: './test-value-bind.component.html',
styleUrls: ['./test-value-bind.component.css']
})
export class TestValueBindComponent implements OnInit {
public imgSrc = './assets/imgs/1.jpg';
constructor() { }
ngOnInit() {
}
}- test-value-bind.component.html
<div class="panel panel-primary">
<div class="panel-heading">单向值绑定</div>
<div class="panel-body">
<img [src]="imgSrc" />
</div>
</div>事件绑定：()
- test-event-bind-component.ts
@Component({
selector: 'app-test-event-binding',
templateUrl: './test-event-binding.component.html',
styleUrls: ['./test-event-binding.component.css']
})
export class TestEventBindingComponent implements OnInit {
constructor() { }
ngOnInit() {
}
public btnClick(event: any): void {
console.log(event + '测试事件绑定！');
}
}- test-event-bind.component.html
<div class="panel panel-primary">
<div class="panel-heading">事件绑定</div>
<div class="panel-body">
<button class="btn btn-success" (click)="btnClick($event)">点击按钮</button>
</div>
</div>双向绑定：[()]
- test-twoway-binding.component.ts
@Component({
selector: 'app-test-twoway-binding',
templateUrl: './test-twoway-binding.component.html',
styleUrls: ['./test-twoway-binding.component.css']
})
export class TestTwowayBindingComponent implements OnInit {
public fontSizePx = 14;
constructor() { }
ngOnInit() {
}
}- test-twoway-binding.component.html
<div class="panel panel-primary">
<div class="panel-heading">双向绑定</div>
<div class="panel-body">
<app-font-resizer [(size)]="fontSizePx"></app-font-resizer>
<div [style.font-size.px]="fontSizePx">Resizable Text</div>
</div>
</div>- font-resizer.component.ts
@Component({
selector: 'app-font-resizer',
templateUrl: './font-resizer.component.html',
styleUrls: ['./font-resizer.component.css']
})
export class FontResizerComponent implements OnInit {
@Input()
size: number | string;
@Output()
sizeChange = new EventEmitter<number>();
constructor() { }
ngOnInit() {
}
decrement(): void {
this.resize(-1);
}
increment(): void {
this.resize(+1);
}
resize(delta: number) {
this.size = Math.min(40, Math.max(8, +this.size + delta));
this.sizeChange.emit(this.size);
}
}- font-resizer.component.html
<div style="border: 2px solid #333">
<p>这是子组件</p>
<button (click)="decrement()" title="smaller">-</button>
<button (click)="increment()" title="bigger">+</button>
<label [style.font-size.px]="size">FontSize: {{size}}px</label>
</div>内置结构型指令
*ngIf
- test-ng-if.component.ts
@Component({
selector: 'app-test-ng-if',
templateUrl: './test-ng-if.component.html',
styleUrls: ['./test-ng-if.component.css']
})
export class TestNgIfComponent implements OnInit {
isShow = true;
constructor() { }
ngOnInit() {
}
}- test-ng-if.component.html
<div class="panel panel-primary">
<div class="panel-heading">*ngIf的用法</div>
<div class="panel-body">
<p *ngIf="isShow" style="background-color:#ff3300">显示内容</p>
</div>
</div>*ngFor
- test-ng-for.component.ts
@Component({
selector: 'app-test-ng-for',
templateUrl: './test-ng-for.component.html',
styleUrls: ['./test-ng-for.component.css']
})
export class TestNgForComponent implements OnInit {
races = [
{name: 'star'},
{name: 'kevin'},
{name: 'kent'}
];
constructor() { }
ngOnInit() {
}
}- test-ng-for.component.html
<div class="panel panel-primary">
<div class="panel-heading">*ngFor用法</div>
<div class="panel-body">
<h3>名字列表</h3>
<ul>
<li *ngFor="let name of names;let i=index;">
{{i}}-{{name.name}}
</li>
</ul>
</div>
</div>ngSwitch
- test-ng-switch.component.ts
@Component({
selector: 'app-test-ng-switch',
templateUrl: './test-ng-switch.component.html',
styleUrls: ['./test-ng-switch.component.css']
})
export class TestNgSwitchComponent implements OnInit {
status = 1;
constructor() { }
ngOnInit() {
}
}- test-ng-switch.component.html
<div class="panel panel-primary">
<div class="panel-heading">ngSwitch用法</div>
<div class="panel-body">
<div [ngSwitch]="status">
<p *ngSwitchCase="0">Good</p>
<p *ngSwitchCase="1">Bad</p>
<p *ngSwitchDefault>Exception</p>
</div>
</div>
</div>内置属性型指令
HTML 属性与 DOM 属性关系
- 少量的 HTML 属性与 DOM 属性之间有着一对一的映射关系， 如 id；
- 有些 HTML 属性没有对应的 DOM 属性， 如 colspan；
- 有些 DOM 属性没有对应的 HTML 属性， 如 textContent；
- 就算名字相同， HTML 属性和 DOM 属性也不是同一样东西；
- HTML 属性的值指定了初始值， DOM 属性的值表示当前值； HTML 属性的值不可改变， DOM 属性的值可以改变。
- 模板绑定是通过 DOM 属性和事件来工作的， 而不是 HTML 属性。
注意： 插值表达式与属性绑定是同一个东西， 插值表达式属于 DOM 属性绑定。
NgClass
- test-ng-class.component.ts
@Component({
selector: 'app-test-ng-class',
templateUrl: './test-ng-class.component.html',
styleUrls: ['./test-ng-class.component.scss']
})
export class TestNgClassComponent implements OnInit {
public currentClasses: {};
public canSave = true;
public isUnchanged = true;
public isSpecial = true;
constructor() { }
ngOnInit() {
this.currentClasses = {
'saveable': this.canSave,
'modified': this.isUnchanged,
'special': this.isSpecial
};
}
}- test-ng-class.component.html
<div class="panel panel-primary">
<div class="panel-heading">NgClass用法</div>
<div class="panel-body">
<div [ngClass]="currentClasses">设置多个样式</div>
<div [class.modified]='true'></div>
</div>
</div>- test-ng-class.component.less
.saveable {
font-size: 18px;
}
.modified {
font-weight: bold;
}
.special {
background-color: #ff3300;
}NgStyle
- test-ng-style.component.ts
@Component({
selector: 'app-test-ng-style',
templateUrl: './test-ng-style.component.html',
styleUrls: ['./test-ng-style.component.css']
})
export class TestNgStyleComponent implements OnInit {
currentStyles: { };
canSave = false;
isUnchanged = false;
isSpecial = false;
constructor() { }
ngOnInit() {
this.currentStyles = {
'font-style': this.canSave ? 'italic' : 'normal',
'font-weight': !this.isUnchanged ? 'bold' : 'normal',
'font-size': this.isSpecial ? '36px' : '12px'
};
}
}- test-ng-style.component.html
<div class="panel panel-primary">
<div class="panel-heading">NgStyle用法</div>
<div class="panel-body">
<div [ngStyle]="currentStyles">
用NgStyle批量修改内联样式！
</div>
<div [style.font-size]="isSpecial? '36px' : '12px'"></div>
</div>
</div>NgModel
- test-ng-model.component.ts
@Component({
selector: 'app-test-ng-model',
templateUrl: './test-ng-model.component.html',
styleUrls: ['./test-ng-model.component.css']
})
export class TestNgModelComponent implements OnInit {
name = 'kevin';
constructor() { }
ngOnInit() {
}
}- test-ng-model.component.html
<div class="panel panel-primary">
<div class="panel-heading">NgModel的用法</div>
<div class="panel-body">
<p class="text-danger">ngModel只能用在表单类的元素上面</p>
<input type="text" name="name" [(ngModel)]="name">
</div>
</div>小工具
管道
Angular 内置的常用管道：
- uppercase 与 lowercase
uppercase 将字母转换成大写 {{‘aaa’ | uppercase}} lowercase 将字母转换成小写 {{‘BBB’ | lowercase}}
- Date
{{ birthday | date: ‘yyyy-MM-dd HH:mm:ss’}}
- number
{{ pi | number: ‘2.2-2’}}
2.2-2: 表示是保留 2 位整数和 2 位小数。
2-2: 表示最少 2 位小数，最大 2 位小数。
- 示例
test-pipe.component.ts
@Component({
selector: 'app-test-pipe',
templateUrl: './test-pipe.component.html',
styleUrls: ['./test-pipe.component.css']
})
export class TestPipeComponent implements OnInit {
currentTime: Date = new Date();
str = 'aaa';
money = 34.567;
constructor() {
}
ngOnInit() {
window.setInterval(
() => { this.currentTime = new Date() }
, 1000);
}
}test-pipe.component.html
<div class="panel panel-primary">
<div class="panel-heading">管道的用法</div>
<div class="panel-body">
{{ currentTime | date:'yyyy-MM-dd HH:mm:ss' }}
</div>
<div class="panel-body">
{{ str | uppercase }}
</div>
<div class="panel-body">
{{ money | number: '2.2-2' }}
</div>
</div>非空断言
- test-not-null-assert.component.ts
@Component({
selector: 'app-test-safe-nav',
templateUrl: './test-not-null-assert.component.html',
styleUrls: ['./test-not-null-assert.component.css']
})
export class TestSafeNavComponent implements OnInit {
public currentValue: any = null;
constructor() { }
ngOnInit() {
}
}- test-not-null-assert.component.html
<div class="panel panel-primary">
<div class="panel-heading">安全取值</div>
<div class="panel-body">
名字：{{currentValue?.name}}
</div>
</div>更多编程相关知识，可访问：编程教学！！
