Question

我正在尝试使用Angular Cli 6评估项目的框架。我对材料数据表示例https://material.angular.io/components/table/overview

感到困惑

如果我的data-json（PeriodicElement）缺少字段，我不怎么处理情况。例如，如果第一个json对象中缺少字段

symbol: 'H'

。 Angular在给我

error:  Property 'symbol' is missing in symbol

该表应出现，并且当缺少字段时，该表应为空字符串（表中为空字符串）或null。



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

    export interface PeriodicElement {
        name: string;
        position: number;
        weight: number;
        symbol: string;
    }

    const ELEMENT_DATA: PeriodicElement[] = [
        {position: 1, name: 'Hydrogen', weight: 1.0079, symbol: 'H'},
        {position: 2, name: 'Helium', weight: 4.0026, symbol: 'He'},
        {position: 3, name: 'Lithium', weight: 6.941, symbol: 'Li'},
        {position: 4, name: 'Beryllium', weight: 9.0122, symbol: 'Be'},
        {position: 5, name: 'Boron', weight: 10.811, symbol: 'B'},
        {position: 6, name: 'Carbon', weight: 12.0107, symbol: 'C'},
        {position: 7, name: 'Nitrogen', weight: 14.0067, symbol: 'N'},
        {position: 8, name: 'Oxygen', weight: 15.9994, symbol: 'O'},
        {position: 9, name: 'Fluorine', weight: 18.9984, symbol: 'F'},
        {position: 10, name: 'Neon', weight: 20.1797, symbol: 'Ne'},
    ];

    /**
     * @title Basic use of ``
     */
    @Component({
       selector: 'table-basic-example',
       styleUrls: ['table-basic-example.css'],
       templateUrl: 'table-basic-example.html',
    })
    export class TableBasicExample {
       displayedColumns: string[] = ['position', 'name', 'weight', 'symbol'];
        dataSource = ELEMENT_DATA;
    }

Answer 1

根据您的情况，使用带有可选参数的接口可能更方便

export interface PeriodicElement {
        name: string;
        position: number;
        weight: number;
        symbol?: string;
}

Angular数据表中缺少字段时出错

1 个答案: