模板中的{{call()}}是否多次执行方法块? [英] {{ call() }} in template executes the method block multiple times?

问题描述

在这里，test方法中的语句被多次调用.为什么会这样呢? AngularJS2是否多次创建DOM?

Here the statements in test method is called multiple times. Why is this happening? Is DOM is recreated by AngularJS2 multiple times?

import { Component } from '@angular/core';

@Component({
  selector: 'my-app',
  template: `<div>Method Call {{test()}}</div>>`
})

export class AppComponent { 
    name = 'Angular';
    test() {
       console.log("Test is called");
    }
}

每次Angular运行更改检测时，都会评估

推荐答案

{{test()}}.

不建议从视图绑定到函数或方法.最好将方法调用的结果分配给一个属性，然后绑定到该属性.

Binding to function or methods from the view is discouraged. Prefer assigning the result of the method call to a property and bind to this property instead.

@Component({
  selector: 'my-app',
  template: `<div>Method Call {{someValue}}</div>>`
})

export class AppComponent { 
    ngOnInit() {
      this.test();
    }
    name = 'Angular';
    test() {
       this.someValue = "Test is called";
    }
}

这篇关于模板中的{{call()}}是否多次执行方法块?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！