<div class="red">red</div>  //这里类名为red
<div [class]="red">red</div> //这里类名为blue,就是说有方括号右侧为表达式
 
//组件中
red: string = "blue";

<div (click)="go()">gogo</div>  //圆括号里面放事件
 
//组件类
go() {
 //表达式...
}

<div>{{good}}</div>  //<div>你好</div> 
 
//组件类
good: string = "你好";

tes: string = "World";
test: string = `Hello ${goo}`;  //test: string = "Hello World";

<input [(ngModel)]='test_input' /> // value= 'testNgClick'
 
//组件中 
test_input: any = 'testNgClick';