关于前端:数组的-splice-slice方法

splice 办法

构造1: arr.splice(start,deletedCount) 纯删除从start下标开始,删除几个构造2: arr.splice(start,deletedCount,item) 替换从start下标开始,删除几个,并在该地位增加item构造3: arr.splice(start,0,item) 纯增加从start下标开始,删除0个,并在该地位增加item,start开始全副往后挪动let arr = [1,2,6,7,8];arr.splice(2,0,3,4,5);//arr = [1,2,3,4,5,6,7,8];

slice 办法

该办法能够从数组中截取指定的字段,返回进去返回值:返回截取进去的字段,放到新的数组中,不扭转原数组构造1:arr.slice(start,end) ;从start下标开始截取,始终到end完结,不包含endlet arr = [0,1,2,3,4,5,6,7];let newArr = arr.slice(0,3)//newArr = [0,1,2];构造2:arr.slice(start) ;从start下标开始截取,始终到最初let arr = [0,1,2,3,4,5,6,7];let newArr = arr.slice(2)//newArr = [2，3，4，5，6，7];构造3:arr.slice( ) ;全副截取let arr = [0,1,2,3,4,5,6,7];let newArr = arr.slice()//newArr = [0,1,2,3,4,5,6,7];