let the_string = "Swift"
let resultString = "\(the_string) is a new Programming Language"

let the_string = "Swift"
let resultString = "\(the_string) is a new Programming Language"

这也会起作用:

var string = "swift"
var resultStr = string + " is a new Programming Language"

非常简单:

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

你也可以在Swift中使用stringByAppendingFormat。

var finalString : NSString = NSString(string: "Hello")
finalString = finalString.stringByAppendingFormat("%@", " World")
print(finalString) //Output:- Hello World
finalString = finalString.stringByAppendingFormat("%@", " Of People")
print(finalString) //Output:- Hello World Of People

Xcode不接受与普通字符串一起添加的可选字符串。我写了这个扩展来解决这个问题:

extension String {
    mutating func addString(str: String) {
        self = self + str
    }
}

然后你可以这样称呼它:

var str1: String?
var str1 = "hi"
var str2 = " my name is"
str1.addString(str2)
println(str1) //hi my name is

然而，你现在也可以这样做:

var str1: String?
var str1 = "hi"
var str2 = " my name is"
str1! += str2