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
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"]
let str = "one two"
let strSplit = str.characters.split(" ").map(String.init) // returns ["one", "two"]
Xcode 7.2（7C68）
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)
}
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"
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))
