如何将Swift数组转换为字符串?

如果数组包含字符串，你可以使用String的join方法:

var array = ["1", "2", "3"]


let stringRepresentation = "-".join(array) // "1-2-3"

在斯威夫特2:

var array = ["1", "2", "3"]


let stringRepresentation = array.joinWithSeparator("-") // "1-2-3"

如果您想使用特定的分隔符(连字符、空格、逗号等)，这可能很有用。

否则，你可以简单地使用description属性，它返回数组的字符串表示形式:

let stringRepresentation = [1, 2, 3].description // "[1, 2, 3]"

提示:任何实现Printable协议的对象都有一个description属性。如果你在自己的类/结构中采用该协议，你也可以使它们打印友好

在斯威夫特3

• join变为joined，示例为[nil, "1", "2"].flatMap({$0}).joined()
• joinWithSeparator变成joined(separator:)(仅对字符串数组可用)

在斯威夫特4

var array = ["1", "2", "3"]
array.joined(separator:"-")

Swift等价于你所描述的是字符串插值。如果你考虑的是JavaScript执行"x" + array，那么在Swift中等价的是"x\(array)"。

一般来说，字符串插值和Printable协议之间有一个重要的区别。只有特定的类符合Printable。每一个类可以以某种方式插入字符串。这在编写泛型函数时很有帮助。你不必局限于Printable类。

Swift 2.0 Xcode 7.0 beta 6以后使用joinWithSeparator()代替join():

var array = ["1", "2", "3"]
let stringRepresentation = array.joinWithSeparator("-") // "1-2-3"

joinWithSeparator被定义为SequenceType的扩展

extension SequenceType where Generator.Element == String {
/// Interpose the `separator` between elements of `self`, then concatenate
/// the result.  For example:
///
///     ["foo", "bar", "baz"].joinWithSeparator("-|-") // "foo-|-bar-|-baz"
@warn_unused_result
public func joinWithSeparator(separator: String) -> String
}

我的工作在NSMutableArray与componentsJoinedByString

var array = ["1", "2", "3"]
let stringRepresentation = array.componentsJoinedByString("-") // "1-2-3"

使用Swift 5，根据您的需要，您可以选择以下Playground示例代码之一来解决您的问题。

将一个__abc0数组转换为不带分隔符的String:

let characterArray: [Character] = ["J", "o", "h", "n"]
let string = String(characterArray)


print(string)
// prints "John"

将String数组转换为不带分隔符的String:

let stringArray = ["Bob", "Dan", "Bryan"]
let string = stringArray.joined(separator: "")


print(string) // prints: "BobDanBryan"

将String数组转换为String，在单词之间使用分隔符:

let stringArray = ["Bob", "Dan", "Bryan"]
let string = stringArray.joined(separator: " ")


print(string) // prints: "Bob Dan Bryan"

将String数组转换为字符之间带有分隔符的String:

let stringArray = ["car", "bike", "boat"]
let characterArray = stringArray.flatMap { $0 }
let stringArray2 = characterArray.map { String($0) }
let string = stringArray2.joined(separator: ", ")


print(string) // prints: "c, a, r, b, i, k, e, b, o, a, t"

将__abc0数组转换为数字之间带有分隔符的String:

let floatArray = [12, 14.6, 35]
let stringArray = floatArray.map { String($0) }
let string = stringArray.joined(separator: "-")


print(string)
// prints "12.0-14.6-35.0"

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

可以使用print函数打印任何对象

或使用\(name)将任何对象转换为字符串。

例子:

let array = [1,2,3,4]


print(array) // prints "[1,2,3,4]"


let string = "\(array)" // string == "[1,2,3,4]"
print(string) // prints "[1,2,3,4]"

在Swift 2.2中，你可能不得不将数组转换为NSArray来使用componentsJoinedByString("，")

let stringWithCommas = (yourArray as NSArray).componentsJoinedByString(",")

斯威夫特3

["I Love","Swift"].joined(separator:" ") // previously joinWithSeparator(" ")

对于swift 3:

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
if textField == phoneField
{
let newString = NSString(string: textField.text!).replacingCharacters(in: range, with: string)
let components = newString.components(separatedBy: NSCharacterSet.decimalDigits.inverted)


let decimalString = NSString(string: components.joined(separator: ""))
let length = decimalString.length
let hasLeadingOne = length > 0 && decimalString.character(at: 0) == (1 as unichar)


if length == 0 || (length > 10 && !hasLeadingOne) || length > 11
{
let newLength = NSString(string: textField.text!).length + (string as NSString).length - range.length as Int


return (newLength > 10) ? false : true
}
var index = 0 as Int
let formattedString = NSMutableString()


if hasLeadingOne
{
formattedString.append("1 ")
index += 1
}
if (length - index) > 3
{
let areaCode = decimalString.substring(with: NSMakeRange(index, 3))
formattedString.appendFormat("(%@)", areaCode)
index += 3
}
if length - index > 3
{
let prefix = decimalString.substring(with: NSMakeRange(index, 3))
formattedString.appendFormat("%@-", prefix)
index += 3
}


let remainder = decimalString.substring(from: index)
formattedString.append(remainder)
textField.text = formattedString as String
return false
}
else
{
return true
}
}

由于没有人提到reduce，下面是:

[0, 1, 1, 0].map {"\($0)"}.reduce("") { $0 + $1 } // "0110"

本着函数式编程的精神🤖

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。

为Array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
}
}
}

在Swift 4中

let array:[String] = ["Apple", "Pear ","Orange"]


array.joined(separator: " ")

如果你想在数组中丢弃空字符串。

["Jet", "Fire"].filter { !$0.isEmpty }.joined(separator: "-")

如果你也想过滤nil值:

["Jet", nil, "", "Fire"].flatMap { $0 }.filter { !$0.isEmpty }.joined(separator: "-")

String(tobeFormattedString)

// 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!)

如果你有字符串数组列表，那么转换为Int

let arrayList = list.map { Int($0)!}
arrayList.description

它会给你字符串值

对于任何元素类型

extension Array {


func joined(glue:()->Element)->[Element]{
var result:[Element] = [];
result.reserveCapacity(count * 2);
let last = count - 1;
for (ix,item) in enumerated() {
result.append(item);
guard ix < last else{ continue }
result.append(glue());
}
return result;
}
}

试试这个:

let categories = dictData?.value(forKeyPath: "listing_subcategories_id") as! NSMutableArray
let tempArray = NSMutableArray()
for dc in categories
{
let dictD = dc as? NSMutableDictionary
tempArray.add(dictD?.object(forKey: "subcategories_name") as! String)
}
let joinedString = tempArray.componentsJoined(by: ",")

当您想要将结构类型的列表转换为字符串时，请使用此方法

struct MyStruct {
var name : String
var content : String
}


let myStructList = [MyStruct(name: "name1" , content: "content1") , MyStruct(name: "name2" , content: "content2")]

然后像这样隐藏你的数组

let myString = myStructList.map({$0.name}).joined(separator: ",")

将产生===>"name1,name2"

现在，在iOS 13+和macOS 10.15+中，我们可以使用ListFormatter:

let formatter = ListFormatter()


let names = ["Moe", "Larry", "Curly"]
if let string = formatter.string(from: names) {
print(string)
}

这将生成一个漂亮的自然语言字符串表示列表。美国用户将看到:

老谋子，拉里和卷毛

它将支持任何语言，其中(a)你的应用程序已本地化;并且(b)配置了用户的设备。例如，一个德国用户的应用程序支持德语本地化，他会看到:

老谋子，拉里和卷毛

当你也有struct数组时，你可以使用joined()来获得一个字符串。

struct Person{
let name:String
let contact:String
}

你可以使用map() &joined()

PersonList.map({"\($0.name) - \($0.contact)"}).joined(separator: " | ")

输出:

Jhon - 123 | Mark - 456 | Ben - 789

如果你想转换自定义对象数组为字符串或逗号分隔字符串(csv)，你可以使用

 var stringIds = (self.mylist.map{$0.id ?? 0}).map{String($0)}.joined(separator: ",")

归功于:urvish modi 职位:将int数组转换为逗号分隔的字符串 < / p >

你可以使用循环来完成这个任务。或者使用地图。

通过映射:

let array = ["one" , "two" , "three"]
    

array.map({$0}).joined(seperator : ",")

在分隔符中，你可以修改字符串。

Output-> ("one,two,three")