Question

我正在尝试从字符串中获取字符串数组。它是我想要迭代的单独符号。

 let chars = binaryString.characters.map { String($0) }

    for (index, item) in chars {

      let activeDay = (index, item)

      switch activeDay {
      case (Days.Monday.rawValue, "1"):
        mondayLabel.textColor = UIColor.blackColor()
      case (Days.Monday.rawValue, "0"):
        mondayLabel.textColor = UIColor.grayColor()

但是Xcode说Expression type '[String]' is ambiguous without more context

Answer 1

尝试使用Swift的所有好处：

var binaryString = "12312312312312312"

let characters = Array(binaryString.characters)

//Values
for char in characters {
    print(char)
}

//Keys and values
for (index, item) in characters.enumerate() {
    print(index)
    print(item)
}

Answer 2

要使代码生效，您需要将enumerate()添加到chars数组中：

for (index, item) in chars.enumerate() {
    ...

生成的chars数组属于[String]类型，并且尝试将其枚举为索引对象元组会产生错误。

Swift如何迭代字符串中的符号

2 个答案: