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Swift如何从字符串中迭代符号_Swift - Fatal编程技术网

Swift如何从字符串中迭代符号

Swift如何从字符串中迭代符号,swift,Swift,我试图从字符串中获取字符串数组。我想迭代的是不同的符号 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

我试图从字符串中获取字符串数组。我想迭代的是不同的符号

 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,如果没有更多的上下文,表达式类型“[String]”是不明确的

尝试使用Swift的所有优点:

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)
}

尽量利用Swift的所有优点:

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)
}

要使代码正常工作,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,尝试将其枚举为索引对象元组会产生错误

要使代码正常工作,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,尝试将其枚举为索引对象元组会产生错误

可能的重复可能的重复