数组 – Swift数组加入EXC_BAD_ACCESS

var ar1 = [1,2,3]
var ar2 = [5,6,7]
var res = ar1.join(ar2)

有人遇到过这个问题吗？任何解决方案或建议？

var ar1 = [1,2,3]
var ar2 = [5,6,7]
var res = ar1 + ar2

您通常会使用join()通过在第一级元素之间插入另一个数组中的元素来展平两级数组：

var ar1 = [1,2,3]
var ar2 = [[4,5,6],[7,8,9],[10,11,12]]
let res = ar1.join(ar2) // [4, 5, 6, 1, 2, 3, 7, 8, 9, 1, 2, 3, 10, 11, 12]

该函数也以相同的方式对字符串起作用：

let ar1 = ["1","2","3"]
let res = ".!?".join(ar1) // "1.!?2.!?3"