class SpaceRemover
{
    func SpaceRemover(str :String)->String
    {
        var array = Array(str)
        var i = array.count
        while(array.last == " ")
        {
            var array1 = [Character]()
            for item in  0...i - 1
            {
                array1.append(array[item])
            }
            i = i - 1
            array = array1
            print(array1)
            print(array)

        }

        var arraySecond = array
        var j = arraySecond.count

        while(arraySecond.first == " ")
        {
            var array2 = [Character]()
            if j > 1
            {
                for item in 1..<j
                {
                    array2.append(arraySecond[item])
                }
            }
            j = j - 1
            arraySecond = array2
            print(array2)
            print(arraySecond)

        }
        print(arraySecond)
        return String(arraySecond)
    }
}

从技术上讲，这不是对原始问题的回答，但由于这里的许多帖子都给出了删除所有空白的答案，这里是一个更新的、更简洁的版本:

let stringWithouTAnyWhitespace = string.filter {!$0.isWhitespace}

尝试函数式编程来删除空白:

extension String {
  func whiteSpacesRemoved() -> String {
    return self.filter { $0 != Character(" ") }
  }
}

我会使用这个扩展，以灵活和模仿其他集合如何做到这一点:

extension String {
    func filter(pred: Character -> Bool) -> String {
        var res = String()
        for c in self.characters {
            if pred(c) {
                res.append(c)
            }
        }
        return res
    }
}

"this is a String".filter { $0 != Character(" ") } // "thisisaString"

嗨，这可能有点晚，但值得一试。这是一个游乐场的文件。你可以让它成为一个字符串扩展名。

这是在Swift 5.3中编写的

方法1:

var str = "\n \tHello, playground       "
if let regexp = try? NSRegularExpression(pattern: "^\\s+", options: NSRegularExpression.Options.caseInsensitive) {
    let mstr = NSMutableString(string: str)
    regexp.replaceMatches(in: mstr, options: [], range: NSRange(location: 0, length: str.count), withTemplate: "")
    str = mstr as String
}

Result: "Hello, playground       "

方法2:

if let c = (str.first { !($0 == " " || $0 == "\t" || $0 == "\n") }) {
    if let nonWhiteSpaceIndex = str.firstIndex(of: c) {
        str.replaceSubrange(str.startIndex ..< nonWhiteSpaceIndex, with: "")
    }
}

Result: "Hello, playground       "

羽毛球猫的答案的Swift 3版本

extension String {
    func replace(_ string:String, replacement:String) -> String {
        return self.replacingOccurrences(of: string, with: replacement, options: NSString.CompareOptions.literal, range: nil)
    }

    func removeWhitespace() -> String {
        return self.replace(" ", replacement: "")
    }
}