es6 数组插入删除查找过滤

var
data=[
      {key:'1',title:'a',parentId:'-1'},
      {key:'2',title:'b',parentId:'-1'},
      {key:'3',title:'c',parentId:'-1'},
    ]
   
   // data.splice(1,1)删除
   //插入 data.splice(1,0,{key:'2',title:'b',parentId:'-1'}) ;
   
   //查找 var r= data.findIndex(item => item.key ==='2');
    //查找 var r= data.filter (item => item.key ==='2');