js every some 遍历函数理解

时间:2021-04-04 05:45:49

1、every

let arr = [0, 1, 2, 3, 4, 5];

let result = arr.every((item, index) => {

  return item >= 0

})

结果: result = true (所有数值都大于或等于0)

let result = arr.every((item, index) => {

  return item > 0

})
结果: result = false(不是所有数值都大于0)

2、some

let arr = [0, 1, 2, 3, 4, 5];

let result = arr.some((item, index) => {

  return item >= 5

})

结果: result = true(有一些数值大于或等于5)

let arr = [0, 1, 2, 3, 4, 5];

let result = arr.some((item, index) => {

  return item > 5

})

结果: result = false(没有数值大于5)