angular6 在ngFor遍历后台数据时如何去掉最后一个值的逗号

〇、Tip

angular在 *ngFor时会获得对奇数、偶数、第一个、最后一个的index

一、思路

• angular在ngFor的时候可以获取到当前遍历item的index
• angular 的ngFor就给到了奇偶、索引

*ngFor="let reg of item.assetclass;let i = index; let last = last;let even =even;let odd=odd;"

• 三元判断是否是最后一个，是最后一个就去掉逗号，否则就加上

二、data数据

  data = {
    listAllGrids: [
      {
        id: 1,
        title: 'Classification of SD for trade party 2',
        category: 'Value accuracy',
        regulatory: 'CFTC.45.2,CFTC.45.4,CFTC.45.7',
        assetclass: ['CO', 'CR', 'EQ', 'IR'],
        activity: 'Issue confirmed',
        impactedrecords: 32000,
        __typename: 'GridType',
      },
      {
        id: 2,
        title: 'Classification of non-SD for trade party 2',
        category: 'Value accuracy',
        regulatory: 'CFTC.45.2',
        assetclass: ['CO', 'IR'],
        activity: 'Review required',
        impactedrecords: 13000,
        __typename: 'GridType',
      },
      {
        id: 3,
        title: 'Unique LEI for each party',
        category: 'Value accuracy',
        regulatory: 'CFTC.45.2',
        assetclass: ['CO','EQ'],
        activity: 'No issue',
        impactedrecords: 25400,
        __typename: 'GridType',
      },
      {
        id: 4,
        title: 'Mandatory clearing indicator',
        category: 'Field completeness',
        regulatory: 'CFTC.45.2,CFTC.45.9',
        assetclass: ['CO'],
        activity: 'Review required',
        impactedrecords: 56000,
        __typename: 'GridType',
      },
      {
        id: 5,
        title: 'Mandatory clearing product - cleared or rework',
        category: 'Over-reporting',
        regulatory: 'CFTC.45.2,CFTC.45.7',
        assetclass: ['EQ'],
        activity: 'No issue',
        impactedrecords: 7800,
        __typename: 'GridType',
      },
    ],
  };

三、html页面

  
    {{reg}}{{last ? '' : ','}}