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
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)
}
其他回答
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", "--"]
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
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]
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"]
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)
