我知道如何通过编程来做到这一点，但我相信有一种内置的方式……
我使用过的每种语言都有某种对象集合的默认文本表示，当您试图将Array与字符串连接起来或将其传递给print()函数等时，它会吐出这些文本表示。苹果的Swift语言是否有一种内置的方式，可以轻松地将数组转换为字符串，或者我们总是必须显式地对数组进行字符串化?
当前回答
修改一个可选/非可选字符串数组
//Array of optional Strings
let array : [String?] = ["1",nil,"2","3","4"]
//Separator String
let separator = ","
//flatMap skips the nil values and then joined combines the non nil elements with the separator
let joinedString = array.flatMap{ $0 }.joined(separator: separator)
//Use Compact map in case of **Swift 4**
let joinedString = array.compactMap{ $0 }.joined(separator: separator
print(joinedString)
这里是flatMap, compactMap跳过数组中的nil值，并附加其他值以给出一个连接字符串。
其他回答
let arrayTemp :[String] = ["Mani","Singh","iOS Developer"]
let stringAfterCombining = arrayTemp.componentsJoinedByString(" ")
print("Result will be >>> \(stringAfterCombining)")
结果将>>> Mani Singh iOS开发者
为数组创建扩展:
extension Array {
var string: String? {
do {
let data = try JSONSerialization.data(withJSONObject: self, options: [.prettyPrinted])
return String(data: data, encoding: .utf8)
} catch {
return nil
}
}
}
斯威夫特3
["I Love","Swift"].joined(separator:" ") // previously joinWithSeparator(" ")
在Swift 4中
let array:[String] = ["Apple", "Pear ","Orange"]
array.joined(separator: " ")
对于某些语言(如希伯来语或日语)，分隔符可能不是一个好主意。 试试这个:
// Array of Strings
let array: [String] = ["red", "green", "blue"]
let arrayAsString: String = array.description
let stringAsData = arrayAsString.data(using: String.Encoding.utf16)
let arrayBack: [String] = try! JSONDecoder().decode([String].self, from: stringAsData!)
对于其他数据类型，分别为:
// Set of Doubles
let set: Set<Double> = [1, 2.0, 3]
let setAsString: String = set.description
let setStringAsData = setAsString.data(using: String.Encoding.utf16)
let setBack: Set<Double> = try! JSONDecoder().decode(Set<Double>.self, from: setStringAsData!)
