数组分割成数组嵌套对象 （经常使用于分页显示数据）

  //模拟后台调取到的数据
public datas: any = [
    {name: 1}, {name: 1}, {name: 1}, 
    {name: 2}, {name: 2}, {name: 2},
    {name: 3}, {name: 3}, {name: 3},
    {name: 4}, {name: 4}, {name: 4},
    {name: 5}, {name: 5}, {name: 5},
  ];  
  public pages: any = [];     //转化为对象存放在pages数组中

  rows(pagesNum) {
    //在原型上建立一个方法
    (Array as any).prototype.chunk = function (n) { 
      for (var i = 0, temp = [], l = ~~this.length / n; temp.length < l; temp[i++] = this.splice(0, n)) ;
      return temp;
    };                                                    
    //将获取的数据转化以后赋值给this.oages数组
    this.pages= this.datas.chunk(9);
    //-----------------------------------------------------
    //经过传参将this.pages中下标（pagesNum）对应的对象内容打印出来
    let arr = this.pages[pagesNum];
    console.log(arr)
  }