假设我这里有一个字符串：
var fullName: String = "First Last"
我想在空白处拆分字符串，并将值分配给它们各自的变量
var fullNameArr = // something like: fullName.explode(" ")
var firstName: String = fullNameArr[0]
var lastName: String? = fullnameArr[1]
此外，有时用户可能没有姓氏。
当前回答
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"]
其他回答
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
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
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"]
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", "--"]
