最简单的方法是使用组件SeparatedBy:

对于Swift 2：

import Foundation
let fullName : String = "First Last";
let fullNameArr : [String] = fullName.componentsSeparatedByString(" ")

// And then to access the individual words:

var firstName : String = fullNameArr[0]
var lastName : String = fullNameArr[1]

对于Swift 3：

import Foundation

let fullName : String = "First Last"
let fullNameArr : [String] = fullName.components(separatedBy: " ")

// And then to access the individual words:

var firstName : String = fullNameArr[0]
var lastName : String = fullNameArr[1]

只需在fullName上调用componentsSeparatedByString方法

import Foundation

var fullName: String = "First Last"
let fullNameArr = fullName.componentsSeparatedByString(" ")

var firstName: String = fullNameArr[0]
var lastName: String = fullNameArr[1]

Swift 3更新+

import Foundation

let fullName    = "First Last"
let fullNameArr = fullName.components(separatedBy: " ")

let name    = fullNameArr[0]
let surname = fullNameArr[1]

作为WMios答案的替代方案，您还可以使用componentsSeparatedByCharactersSet，这在分隔符（空格、逗号等）较多的情况下非常方便。

使用您的特定输入：

let separators = NSCharacterSet(charactersInString: " ")
var fullName: String = "First Last";
var words = fullName.componentsSeparatedByCharactersInSet(separators)

// words contains ["First", "Last"]

使用多个分隔符：

let separators = NSCharacterSet(charactersInString: " ,")
var fullName: String = "Last, First Middle";
var words = fullName.componentsSeparatedByCharactersInSet(separators)

// words contains ["Last", "First", "Middle"]

Swift的方法是使用全局拆分函数，如下所示：

var fullName = "First Last"
var fullNameArr = split(fullName) {$0 == " "}
var firstName: String = fullNameArr[0]
var lastName: String? = fullNameArr.count > 1 ? fullNameArr[1] : nil

使用Swift 2

在Swift 2中，由于引入了内部CharacterView类型，拆分的使用变得有点复杂。这意味着String不再采用SequenceType或CollectionType协议，您必须改为使用.characts属性来访问String实例的CharacterView类型表示。（注意：CharacterView确实采用SequenceType和CollectionType协议）。

let fullName = "First Last"
let fullNameArr = fullName.characters.split{$0 == " "}.map(String.init)
// or simply:
// let fullNameArr = fullName.characters.split{" "}.map(String.init)

fullNameArr[0] // First
fullNameArr[1] // Last 

Swift 4或更高版本

如果您只需要正确设置人名格式，可以使用PersonNameComponentsFormater。

PersonNameComponentsFormater类提供本地化人名组成部分的表示通过PersonNameComponents对象。使用此类创建本地化当向用户显示人名信息时。

// iOS (9.0 and later), macOS (10.11 and later), tvOS (9.0 and later), watchOS (2.0 and later)
let nameFormatter = PersonNameComponentsFormatter()

let name =  "Mr. Steven Paul Jobs Jr."
// personNameComponents requires iOS (10.0 and later)
if let nameComps  = nameFormatter.personNameComponents(from: name) {
    nameComps.namePrefix   // Mr.
    nameComps.givenName    // Steven
    nameComps.middleName   // Paul
    nameComps.familyName   // Jobs
    nameComps.nameSuffix   // Jr.

    // It can also be configured to format your names
    // Default (same as medium), short, long or abbreviated

    nameFormatter.style = .default
    nameFormatter.string(from: nameComps)   // "Steven Jobs"

    nameFormatter.style = .short
    nameFormatter.string(from: nameComps)   // "Steven"

    nameFormatter.style = .long
    nameFormatter.string(from: nameComps)   // "Mr. Steven Paul Jobs jr."

    nameFormatter.style = .abbreviated
    nameFormatter.string(from: nameComps)   // SJ

    // It can also be use to return an attributed string using annotatedString method
    nameFormatter.style = .long
    nameFormatter.annotatedString(from: nameComps)   // "Mr. Steven Paul Jobs jr."
}

编辑/更新：

Swift 5或更高版本

对于按非字母字符拆分字符串，我们可以使用新的Character属性isLetter：

let fullName = "First Last"

let components = fullName.split{ !$0.isLetter }
print(components)  // "["First", "Last"]\n"

我发现了一个有趣的案例

方法1

var data:[String] = split( featureData ) { $0 == "\u{003B}" }

当我使用此命令从从服务器加载的数据中拆分一些符号时，它可以在模拟器中测试时拆分，并与测试设备同步，但不会在发布应用程序和Ad Hoc中拆分

我花了很多时间来跟踪这个错误，它可能会被某些Swift版本或iOS版本诅咒，或者两者都没有

这也与HTML代码无关，因为我尝试stringByRemovangPercentEncoding，但它仍然不起作用

2015年10月10日新增

在Swift 2.0中，此方法已更改为

var data:[String] = featureData.split {$0 == "\u{003B}"}

方法2

var data:[String] = featureData.componentsSeparatedByString("\u{003B}")

当我使用此命令时，它可以正确分割从服务器加载的相同数据

结论，我真的建议使用方法2

string.componentsSeparatedByString("")

这在Beta 5中再次发生了变化。哭泣！它现在是CollectionType上的一个方法

旧版本：

var fullName = "First Last"
var fullNameArr = split(fullName) {$0 == " "}

新建：

var fullName = "First Last"
var fullNameArr = fullName.split {$0 == " "}

苹果发行说明

或者没有闭包，你可以在Swift 2中这样做：

let fullName = "First Last"
let fullNameArr = fullName.characters.split(" ")
let firstName = String(fullNameArr[0])

对于swift 2，XCode 7.1：

let complete_string:String = "Hello world"
let string_arr =  complete_string.characters.split {$0 == " "}.map(String.init)
let hello:String = string_arr[0]
let world:String = string_arr[1]

空白问题

一般来说，人们会一次又一次地重复这个问题和糟糕的解决方案。这是一个空间吗？“”以及“\n”、“\t”或一些您从未见过的unicode空白字符，在很大程度上是不可见的。虽然你可以逃脱

弱解决方案

import Foundation
let pieces = "Mary had little lamb".componentsSeparatedByString(" ")

如果你需要在现实中动摇你的控制，请观看WWDC视频中的字符串或日期。简而言之，让苹果解决这类平凡的任务几乎总是更好的。

稳健的解决方案：使用NSCharacterSet

IMHO，正确做到这一点的方法是使用NSCharacterSet，因为正如前面所述，您的空白可能不是您所期望的，并且Apple提供了一个空白字符集。要探索提供的各种字符集，请查看Apple的NSCharacterSet开发人员文档，然后，如果不符合您的需要，才可以扩充或构建新的字符集。

NSCharacterSet空白

返回包含Unicode常规中的字符的字符集Z类和字符表（U+0009）。

let longerString: String = "This is a test of the character set splitting system"
let components = longerString.components(separatedBy: .whitespaces)
print(components)

let str = "one two"
let strSplit = str.characters.split(" ").map(String.init) // returns ["one", "two"]

Xcode 7.2（7C68）

根据Swift 2.2

您只需编写2行代码，就会得到拆分字符串。

let fullName = "FirstName LastName"
var splitedFullName = fullName.componentsSeparatedByString(" ")
print(splitedFullName[0])
print(splitedFullName[1]) 

享受。：）

这里是我刚刚构建的一个算法，它将通过数组中的任何字符分割字符串，如果有任何希望保留具有分割字符的子字符串，可以将swall参数设置为true。

Xcode 7.3-Swift 2.2：

extension String {

    func splitBy(characters: [Character], swallow: Bool = false) -> [String] {

        var substring = ""
        var array = [String]()
        var index = 0

        for character in self.characters {

            if let lastCharacter = substring.characters.last {

                // swallow same characters
                if lastCharacter == character {

                    substring.append(character)

                } else {

                    var shouldSplit = false

                    // check if we need to split already
                    for splitCharacter in characters {
                        // slit if the last character is from split characters or the current one
                        if character == splitCharacter || lastCharacter == splitCharacter {

                            shouldSplit = true
                            break
                        }
                    }

                    if shouldSplit {

                        array.append(substring)
                        substring = String(character)

                    } else /* swallow characters that do not equal any of the split characters */ {

                        substring.append(character)
                    }
                }
            } else /* should be the first iteration */ {

                substring.append(character)
            }

            index += 1

            // add last substring to the array
            if index == self.characters.count {

                array.append(substring)
            }
        }

        return array.filter {

            if swallow {

                return true

            } else {

                for splitCharacter in characters {

                    if $0.characters.contains(splitCharacter) {

                        return false
                    }
                }
                return true
            }
        }
    }
}

例子：

"test text".splitBy([" "]) // ["test", "text"]
"test++text--".splitBy(["+", "-"], swallow: true) // ["test", "++" "text", "--"]

斯威夫特2.2添加了错误处理和大写字符串：

func setFullName(fullName: String) {
    var fullNameComponents = fullName.componentsSeparatedByString(" ")

    self.fname = fullNameComponents.count > 0 ? fullNameComponents[0]: ""
    self.sname = fullNameComponents.count > 1 ? fullNameComponents[1]: ""

    self.fname = self.fname!.capitalizedString
    self.sname = self.sname!.capitalizedString
}

大多数这些答案都假设输入包含一个空格，而不是空白，并且只有一个空格。如果你能安全地做出这样的假设，那么（来自bennett的）公认的答案是相当优雅的，也是我在可能的时候会采用的方法。

当我们无法做出这一假设时，一个更稳健的解决方案需要涵盖以下大多数答案没有考虑的情况：

制表符/换行符/空格（空白），包括重复出现的字符前导/尾随空格Apple/Linux（\n）和Windows（\r\n）换行符

为了涵盖这些情况，此解决方案使用正则表达式将所有空格（包括重复出现的字符和Windows换行符）转换为单个空格，然后修剪，然后拆分为单个空格：

斯威夫特3:

let searchInput = "  First \r\n \n \t\t\tMiddle    Last "
let searchTerms = searchInput 
    .replacingOccurrences(
        of: "\\s+",
        with: " ",
        options: .regularExpression
    )
    .trimmingCharacters(in: .whitespaces)
    .components(separatedBy: " ")

// searchTerms == ["First", "Middle", "Last"]

Xcode 8.0/Swift 3

let fullName = "First Last"
var fullNameArr = fullName.components(separatedBy: " ")

var firstname = fullNameArr[0] // First
var lastname = fullNameArr[1] // Last

漫长的道路：

var fullName: String = "First Last"
fullName += " " // this will help to see the last word

var newElement = "" //Empty String
var fullNameArr = [String]() //Empty Array

for Character in fullName.characters {
    if Character == " " {
        fullNameArr.append(newElement)
        newElement = ""
    } else {
        newElement += "\(Character)"
    }
}


var firsName = fullNameArr[0] // First
var lastName = fullNameArr[1] // Last

Swift Dev.4.0（2017年5月24日）

Swift 4（Beta版）中拆分了一个新功能。

import Foundation
let sayHello = "Hello Swift 4 2017";
let result = sayHello.split(separator: " ")
print(result)

输出：

["Hello", "Swift", "4", "2017"]

访问值：

print(result[0]) // Hello
print(result[1]) // Swift
print(result[2]) // 4
print(result[3]) // 2017

Xcode 8.1/Swift 3.0.1

这是多个分隔符与数组的方式。

import Foundation
let mathString: String = "12-37*2/5"
let numbers = mathString.components(separatedBy: ["-", "*", "/"])
print(numbers)

输出：

["12", "37", "2", "5"]

我有一个场景，其中多个控制字符可以出现在我要拆分的字符串中。我只是让苹果处理这一部分，而不是维护一系列这些。

以下功能适用于iOS 10上的Swift 3.0.1：

let myArray = myString.components(separatedBy: .controlCharacters)

字符串处理在Swift中仍然是一个挑战，而且它一直在显著变化，从其他答案中可以看到。希望事情稳定下来，事情会变得更简单。这是在当前3.0版本的Swift中使用多个分隔符的方法。

斯威夫特3:

let chars = CharacterSet(charactersIn: ".,; -")
let split = phrase.components(separatedBy: chars)

// Or if the enums do what you want, these are preferred. 
let chars2 = CharacterSet.alphaNumerics // .whitespaces, .punctuation, .capitalizedLetters etc
let split2 = phrase.components(separatedBy: chars2)

Swift 4使拆分字符变得更加容易，只需为字符串使用新的拆分函数即可。

例子：让s=“嗨，你好”让a=s.split（分隔符：“，”）打印（a）

现在您得到了一个带有“hi”和“hello”的数组。

斯威夫特4

let words = "these words will be elements in an array".components(separatedBy: " ")

我还没有找到能够处理3个或更多组件名称并支持较旧iOS版本的解决方案。

struct NameComponentsSplitter {

    static func split(fullName: String) -> (String?, String?) {
        guard !fullName.isEmpty else {
            return (nil, nil)
        }
        let components = fullName.components(separatedBy: .whitespacesAndNewlines)
        let lastName = components.last
        let firstName = components.dropLast().joined(separator: " ")
        return (firstName.isEmpty ? nil : firstName, lastName)
    }
}

通过测试用例：

func testThatItHandlesTwoComponents() {
    let (firstName, lastName) = NameComponentsSplitter.split(fullName: "John Smith")
    XCTAssertEqual(firstName, "John")
    XCTAssertEqual(lastName, "Smith")
}

func testThatItHandlesMoreThanTwoComponents() {
    var (firstName, lastName) = NameComponentsSplitter.split(fullName: "John Clark Smith")
    XCTAssertEqual(firstName, "John Clark")
    XCTAssertEqual(lastName, "Smith")

    (firstName, lastName) = NameComponentsSplitter.split(fullName: "John Clark Jr. Smith")
    XCTAssertEqual(firstName, "John Clark Jr.")
    XCTAssertEqual(lastName, "Smith")
}

func testThatItHandlesEmptyInput() {
    let (firstName, lastName) = NameComponentsSplitter.split(fullName: "")
    XCTAssertEqual(firstName, nil)
    XCTAssertEqual(lastName, nil)
}

let fullName : String = "Steve.Jobs"
let fullNameArr : [String] = fullName.components(separatedBy: ".")

var firstName : String = fullNameArr[0]
var lastName : String = fullNameArr[1]

雨燕3

let line = "AAA    BBB\t CCC"
let fields = line.components(separatedBy: .whitespaces).filter {!$0.isEmpty}

返回三个字符串AAA、BBB和CCC筛选出空字段处理多个空格和制表字符如果要处理新行，请将.whittespaces替换为.whittespace和新行

var fullName = "James Keagan Michael"
let first = fullName.components(separatedBy: " ").first?.isEmpty == false ? fullName.components(separatedBy: " ").first! : "John"
let last =  fullName.components(separatedBy: " ").last?.isEmpty == false && fullName.components(separatedBy: " ").last != fullName.components(separatedBy: " ").first ? fullName.components(separatedBy: " ").last! : "Doe"

不允许使用相同的名字和姓氏如果全名无效，则取占位符值“John Doe”

在Swift 4中将字符串拆分为数组的步骤。

赋值字符串基于@spling。

注意：variableName.components（separatedBy:“split关键字”）

let fullName: String = "First Last @ triggerd event of the session by session storage @ it can be divided by the event of the trigger."
let fullNameArr = fullName.components(separatedBy: "@")
print("split", fullNameArr)

假设您有一个名为“Hello World”的变量，如果您想将其拆分并存储为两个不同的变量，可以这样使用：

var fullText = "Hello World"
let firstWord = fullText.text?.components(separatedBy: " ").first
let lastWord = fullText.text?.components(separatedBy: " ").last

斯威夫特4

let string = "loremipsum.dolorsant.amet:"

let result = string.components(separatedBy: ".")

print(result[0])
print(result[1])
print(result[2])
print("total: \(result.count)")

输出

loremipsum
dolorsant
amet:
total: 3

Swift 4、Xcode 10和iOS 12更新100%工作

let fullName = "First Last"    
let fullNameArr = fullName.components(separatedBy: " ")
let firstName = fullNameArr[0] //First
let lastName = fullNameArr[1] //Last

有关更多信息，请参阅此处的Apple文档。

我在寻找loosy拆分，例如PHP的分解，其中空序列包含在结果数组中，这对我很有用：

"First ".split(separator: " ", maxSplits: 1, omittingEmptySubsequences: false)

输出：

["First", ""]

在Swift 4.2和Xcode 10中

//This is your str
let str = "This is my String" //Here replace with your string

选项1

let items = str.components(separatedBy: " ")//Here replase space with your value and the result is Array.
//Direct single line of code
//let items = "This is my String".components(separatedBy: " ")
let str1 = items[0]
let str2 = items[1]
let str3 = items[2]
let str4 = items[3]
//OutPut
print(items.count)
print(str1)
print(str2)
print(str3)
print(str4)
print(items.first!)
print(items.last!)

选项2

let items = str.split(separator: " ")
let str1 = String(items.first!)
let str2 = String(items.last!)
//Output
print(items.count)
print(items)
print(str1)
print(str2)

选项3

let arr = str.split {$0 == " "}
print(arr)

选项4

let line = "BLANCHE:   I don't want realism. I want magic!"
print(line.split(separator: " "))
// Prints "["BLANCHE:", "I", "don\'t", "want", "realism.", "I", "want", "magic!"]"

通过Apple文档。。。。

let line = "BLANCHE:   I don't want realism. I want magic!"
print(line.split(separator: " "))
// Prints "["BLANCHE:", "I", "don\'t", "want", "realism.", "I", "want", "magic!"]"

print(line.split(separator: " ", maxSplits: 1))//This can split your string into 2 parts
// Prints "["BLANCHE:", "  I don\'t want realism. I want magic!"]"

print(line.split(separator: " ", maxSplits: 2))//This can split your string into 3 parts

print(line.split(separator: " ", omittingEmptySubsequences: false))//array contains empty strings where spaces were repeated.
// Prints "["BLANCHE:", "", "", "I", "don\'t", "want", "realism.", "I", "want", "magic!"]"

print(line.split(separator: " ", omittingEmptySubsequences: true))//array not contains empty strings where spaces were repeated.
print(line.split(separator: " ", maxSplits: 4, omittingEmptySubsequences: false))
print(line.split(separator: " ", maxSplits: 3, omittingEmptySubsequences: true))

您可以使用此公共函数并添加任何要分隔的字符串

func separateByString(String wholeString: String, byChar char:String) -> [String] {

    let resultArray = wholeString.components(separatedBy: char)
    return resultArray
}

var fullName: String = "First Last"
let array = separateByString(String: fullName, byChar: " ")
var firstName: String = array[0]
var lastName: String = array[1]
print(firstName)
print(lastName)

这是用于swift 4.2在20181206 1610的字符串和CSV文件

var dataArray : [[String]] = []
 let path = Bundle.main.path(forResource: "csvfilename", ofType: "csv")
        let url = URL(fileURLWithPath: path!)
        do {
            let data = try Data(contentsOf: url) 
            let content = String(data: data, encoding: .utf8)
            let parsedCSV = content?.components(separatedBy: "\r\n").map{ $0.components(separatedBy: ";") }
           for line in parsedCSV!
            {
                dataArray.append(line)
           }
        }
        catch let jsonErr {
            print("\n   Error read CSV file: \n ", jsonErr)
        }

            print("\n MohNada 20181206 1610 - The final result is \(dataArray)  \n ")

Swift 5.2的更新和最简单的方式

let paragraph = "Bob hit a ball, the hit BALL flew far after it was hit. Hello! Hie, How r u?"

let words = paragraph.components(separatedBy: [",", " ", "!",".","?"])

这张照片，

[“Bob”，“hit”，“a”，“ball”，“the”，“击球”，“ball”，“fly”，“far”，“after”，“it”，“was”，“hit”，“Hello”，“Hie”，“How”，“u”，“”]

但是，如果要过滤空字符串，

let words = paragraph.components(separatedBy: [",", " ", "!",".","?"]).filter({!$0.isEmpty})

输出

[“Bob”，“hit”，“a”，“ball”，“the”，“命中”，“ball”，“fly”，“far”，“after”，“it”，“was”，“hit”，“Hello”，”Hie“，”How“，”r“，”u“]

但请确保，Foundation已导入。

这直接提供了一个分割部分的数组

var fullNameArr = fullName.components(separatedBy:" ")

那么你可以这样使用，

var firstName: String = fullNameArr[0]
var lastName: String? = fullnameArr[1]

只有拆分才是正确的答案，这里有两个以上空格的差异。

雨燕5

var temp = "Hello world     ni hao"
let arr  = temp.components(separatedBy: .whitespacesAndNewlines)
// ["Hello", "world", "", "", "", "", "ni", "hao"]
let arr2 = temp.components(separatedBy: " ")
// ["Hello", "world", "", "", "", "", "ni", "hao"]
let arr3 = temp.split(whereSeparator: {$0 == " "})
// ["Hello", "world", "ni", "hao"]

在解释Don Vaughn的答案时，我喜欢使用正则表达式。我很惊讶这只是Regex的第二个答案。然而，如果我们能用一个拆分方法而不是多个方法来解决这个问题，那就太好了。

我也受到了米特拉·辛加姆（Mithra Singam）的《答案》（Answer）的启发，排除了所有标点符号和空格。然而，不得不创建一个不允许的角色列表并没有引起我的共鸣。

\w-字母或数字符号的正则表达式。没有标点符号。

let foo = "(..#   Hello,,(---- World   ".split {
    String($0).range(of: #"\w"#, options: .regularExpression) == nil
}
print(foo) // Prints "Hello World"

让我们假设你对Unicode不太满意。ASKII字母和数字怎么样？

let bar = "(..#   Hello,,(---- World   ".split {
    !($0.isASCII && ($0.isLetter || $0.isNumber))
}
print(bar) // Prints "Hello World"

非顶部：

对于搜索如何使用子字符串（而不是字符）拆分字符串的人来说，下面是一个有效的解决方案：

// TESTING
let str1 = "Hello user! What user's details? Here user rounded with space."
let a = str1.split(withSubstring: "user") // <-------------- HERE IS A SPLIT
print(a) // ["Hello ", "! What ", "\'s details? Here ", " rounded with space."]

// testing the result
var result = ""
for item in a {
    if !result.isEmpty {
        result += "user"
    }
    result += item
}
print(str1) // "Hello user! What user's details? Here user rounded with space."
print(result) // "Hello user! What user's details? Here user rounded with space."
print(result == str1) // true

/// Extension providing `split` and `substring` methods.
extension String {
    
    /// Split given string with substring into array
    /// - Parameters:
    ///   - string: the string
    ///   - substring: the substring to search
    /// - Returns: array of components
    func split(withSubstring substring: String) -> [String] {
        var a = [String]()
        var str = self
        while let range = str.range(of: substring) {
            let i = str.distance(from: str.startIndex, to: range.lowerBound)
            let j = str.distance(from: str.startIndex, to: range.upperBound)
            let left = str.substring(index: 0, length: i)
            let right = str.substring(index: j, length: str.length - j)
            a.append(left)
            str = right
        }
        if !str.isEmpty {
            a.append(str)
        }
        return a
    }
    
    /// the length of the string
    public var length: Int {
        return self.count
    }
    
    /// Get substring, e.g. "ABCDE".substring(index: 2, length: 3) -> "CDE"
    ///
    /// - parameter index:  the start index
    /// - parameter length: the length of the substring
    ///
    /// - returns: the substring
    public func substring(index: Int, length: Int) -> String {
        if self.length <= index {
            return ""
        }
        let leftIndex = self.index(self.startIndex, offsetBy: index)
        if self.length <= index + length {
            return String(self[leftIndex..<self.endIndex])
        }
        let rightIndex = self.index(self.endIndex, offsetBy: -(self.length - index - length))
        return String(self[leftIndex..<rightIndex])
    }

}

最简单的解决方案是

let fullName = "First Last"

let components = fullName.components(separatedBy: .whitespacesAndNewlines).compactMap { $0.isEmpty ? nil : $0 }

这将处理不同类型的一行中的多个空格（空格、制表符、换行符等），并且只返回一个两元素数组，您可以更改CharacterSet以包含更多您喜欢的字符，如果您想获得切割符，可以使用正则表达式解码器，这允许您编写正则表达式，该表达式可用于将字符串直接解码到实现解码协议的自己的类/结构中。对于像这样的东西来说，这是过度的，但如果您将其用作更复杂字符串的示例，则可能更有意义。

将字符串拆分为数组的简单方法

var fullName:String=“First Last”；var fullNameArr=fullName.componentsSeparatedByString（“”）var firstName:String=fullNameArr[0]var lastName:String=fullNameArr[1]