斯威夫特5

我们不需要创建扩展，因为ProcessInfo给了我们版本信息。你可以在下面看到iOS的示例代码。

let os = ProcessInfo().operatingSystemVersion

switch (os.majorVersion, os.minorVersion, os.patchVersion) {
case (let x, _, _) where x < 8:
    print("iOS < 8.0.0")

case (8, 0, _):
    print("iOS >= 8.0.0, < 8.1.0")

case (8, _, _):
    print("iOS >= 8.1.0, < 9.0")

case (9, _, _):
    print("iOS >= 9.0.0")

default:
    print("iOS >= 10.0.0")
}

参考:http://nshipster.com/swift-system-version-checking/

我做了帮助函数，从下面的链接转移到swift:

我们如何通过程序检测设备运行的iOS版本?

func SYSTEM_VERSION_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedSame
}

func SYSTEM_VERSION_GREATER_THAN(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedDescending
}

func SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) != NSComparisonResult.OrderedAscending
}

func SYSTEM_VERSION_LESS_THAN(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedAscending
}

func SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) != NSComparisonResult.OrderedDescending
}

它可以这样使用:

SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO("7.0")

斯威夫特4.2

func SYSTEM_VERSION_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedSame
}

func SYSTEM_VERSION_GREATER_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedDescending
}

func SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) != .orderedAscending
}

func SYSTEM_VERSION_LESS_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedAscending
}

func SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) != .orderedDescending
}

注:iOS 8.0及以上版本支持。OS X v10.10及以上版本

var majorVersion: Int    { return NSProcessInfo.processInfo().operatingSystemVersion.majorVersion }
var minorVersion: Int    { return NSProcessInfo.processInfo().operatingSystemVersion.minorVersion }
var patchVersion: Int    { return NSProcessInfo.processInfo().operatingSystemVersion.patchVersion }
var myOSVersion:  String { return NSProcessInfo.processInfo().operatingSystemVersionString        }

细节

Xcode 10.2.1 (10E1001)

链接

OperatingSystemVersion

解决方案

extension OperatingSystemVersion {
    func getFullVersion(separator: String = ".") -> String {
        return "\(majorVersion)\(separator)\(minorVersion)\(separator)\(patchVersion)"
    }
}

let os = ProcessInfo().operatingSystemVersion
print(os.majorVersion)          // 12
print(os.minorVersion)          // 2
print(os.patchVersion)          // 0
print(os.getFullVersion())      // 12.2.0

快4.倍

func iOS_VERSION_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: NSString.CompareOptions.numeric) == ComparisonResult.orderedSame
}

func iOS_VERSION_GREATER_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: NSString.CompareOptions.numeric) == ComparisonResult.orderedDescending
}

func iOS_VERSION_GREATER_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: NSString.CompareOptions.numeric) != ComparisonResult.orderedAscending
}

func iOS_VERSION_LESS_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: NSString.CompareOptions.numeric) == ComparisonResult.orderedAscending
}

func iOS_VERSION_LESS_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: NSString.CompareOptions.numeric) != ComparisonResult.orderedDescending
}

用法:

if iOS_VERSION_GREATER_THAN_OR_EQUAL_TO(version: "11.0") {
    //Do something!
}

附:KVISH回答翻译成Swift 4。x和重命名函数，因为我专门为iOS应用程序使用这个片段。

根据Matt Thompson的回答，这里有一个带有各自单元测试的方法，可以在iOS 7及以上版本(包括iOS 9，不再让你检查NSFoundationNumber)上与Swift和Objective-c一起工作:

+ (BOOL) isAtLeastOSVersion:(NSString *)osVersion
{
    switch ([[UIDevice currentDevice].systemVersion compare:osVersion options:NSNumericSearch]) {
        case NSOrderedSame:
        case NSOrderedDescending:
            return YES;
        default:
            return NO;
    }
}  

.

@interface ANFakeCurrDevice : NSObject
@property (nonatomic, strong) NSString *systemVersion;
@end
@implementation ANFakeCurrDevice
@end


@implementation MyHelperClassUnitTests

- (void)setUp {
    [super setUp];
}

- (void)tearDown {
    [super tearDown];
}

- (void)test_isAtLeastOSVersion
{
    id deviceMock = [OCMockObject niceMockForClass:[UIDevice class]];
    ANFakeCurrDevice *fakeCurrDevice = [ANFakeCurrDevice new];
    fakeCurrDevice.systemVersion = @"99.9.9";
    [[[deviceMock stub] andReturn:fakeCurrDevice] currentDevice];
    XCTAssertTrue([[UIDevice currentDevice].systemVersion isEqualToString:@"99.9.9"]);

    fakeCurrDevice.systemVersion = @"1.0.1";
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"1"]);
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"1.0"]);
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"1.0.1"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"1.0.2"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"1.1.0"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"2"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"2.0"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"2.0.0"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"2.0.1"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"2.1.0"]);


    fakeCurrDevice.systemVersion = @"8.4.0";
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"7.0.1"]);
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"8"]);
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"8.4"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"8.4.1"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"8.4.2"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"9.0"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"9.0.1"]);
    XCTAssertFalse([ANConstants isAtLeastOSVersion:@"9.0.2"]);
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"8.4"] && ![ANConstants isAtLeastOSVersion:@"9.0"]);

    fakeCurrDevice.systemVersion = @"8.4.1";
    XCTAssertTrue([ANConstants isAtLeastOSVersion:@"8.4"] && ![ANConstants isAtLeastOSVersion:@"9.0"]);
}


@end