[英]How to define a function which takes a number as parameter and returns it's square, in angular?
我有一个数字数组,我需要显示这些数字和它们各自的方块。 为此,我需要定义一个函数,该函数将数字作为参数并将其平方作为值返回。我尝试将函数定义为
Numbers:number[]=[2,3,5,7];
square(cm:number):number{
return cm*cm;
}
您需要使用{{square(c1)}}
以便您调用该方法并获取平方值
<h4> List Of Numbers</h4>
<div class="row"*ngFor="let c1 of Numbers;index as i">
<div class="col-1 m-1">
{{i}}
</div>
<div class="col-2 border bg-light m-1">
{{c1}}
</div>
<div class="col-2 border bg-light m-1">
{{square(c1)}}
</div>
<div class="col-1 border fa fa-trash m-1 bg-white" (click)="remove(c1)">
</div>
您可以使用地图功能
var number = [2, 3, 5, 7];
var square = number.map(c=> c*c);
您以错误的方式使用它。在 html 中调用您的函数。
<h4> List Of Numbers</h4>
<div class="row" *ngFor="let c1 of Numbers;index as i">
<div class="col-1 m-1">
{{i}}
</div>
<div class="col-2 border bg-light m-1">
{{c1}}
</div>
<div class="col-2 border bg-light m-1">
{{square(c1)}}
</div>
<div class="col-1 border fa fa-trash m-1 bg-white" (click)="remove(c1)">
</div>
import {Pipe, PipeTransform} from '@angular/core';
@Pipe({
name: 'square',
})
export class SquarePipe implements PipeTransform {
transform(value: any, ...args: any[]): any {
return value * value
}
}
html:
<ng-container *ngFor="let item of iterms">{{ item | square}}</ng-container>
模块.ts:
declarations:[SquarePipe ]
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.