斯威夫特4.2

你也可以使用扩展:

extension Array where Element == String? {
    func compactConcate(separator: String) -> String {
        return self.compactMap {
            if let unwrappedString = $0,
               unwrappedString.isEmpty {
                return nil
            } else {
                return $0
            }
        }
        .joined(separator: separator)
    }
}

Use:

label.text = [m.firstName, m.lastName].compactConcate(separator: " ")

结果:

"The Man"
"The"
"Man"

来打印组合字符串

Println("\(string1)\(string2)")

或String3存储2个字符串组合的输出

let strin3 = "\(string1)\(string2)"

非常简单:

let StringA = "Hello"
let StringB = "World"
let ResultString = "\(StringA)\(StringB)"
println("Concatenated result = \(ResultString)")

var language = "Swift" 
var resultStr = "\(language) is a new programming language"

它被称为字符串插值。 它是用常量，变量，字面量和表达式创建新字符串的方法。 例子:

      let price = 3
      let staringValue = "The price of \(price) mangoes is equal to \(price*price) "

也

let string1 = "anil"
let string2 = "gupta"
let fullName = string1 + string2  // fullName is equal to "anilgupta"
or 
let fullName = "\(string1)\(string2)" // fullName is equal to "anilgupta"

它也意味着串联字符串值。

希望这对你有所帮助。

你可以使用SwiftString (https://github.com/amayne/SwiftString)来做这件事。

"".join(["string1", "string2", "string3"]) // "string1string2string"
" ".join(["hello", "world"]) // "hello world"

免责声明:我写了这个扩展