Try:

NSComparisonResult order = [[UIDevice currentDevice].systemVersion compare: @"3.1.3" options: NSNumericSearch];
if (order == NSOrderedSame || order == NSOrderedDescending) {
    // OS version >= 3.1.3
} else {
    // OS version < 3.1.3
}

+(BOOL)doesSystemVersionMeetRequirement:(NSString *)minRequirement{

// eg  NSString *reqSysVer = @"4.0";


  NSString *currSysVer = [[UIDevice currentDevice] systemVersion];

  if ([currSysVer compare:minRequirement options:NSNumericSearch] != NSOrderedAscending)
  {
    return YES;
  }else{
    return NO;
  }


}

所有的答案看起来都有点太大了。 我只用:

if (SYSTEM_VERSION_GREATER_THAN(@"7.0")){(..CODE...)}
if (SYSTEM_VERSION_EQUAL_TO(@"7.0")){(..CODE...)}
if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"7.0")){(..CODE...)}
if (SYSTEM_VERSION_LESS_THAN(@"7.0")){(..CODE...)}
if (SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(@"7.0")){(..CODE...)}

当然，将@“7.0”替换为所需的操作系统版本。

#define _kisiOS7 ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)

if (_kisiOS7) {
            NSLog(@"iOS7 or greater")
} 
else {
           NSLog(@"Less than iOS7");
}

在您的项目中添加以下Swift代码，并轻松访问iOS版本和设备等信息。

class DeviceInfo: NSObject {

    struct ScreenSize
    {
        static let SCREEN_WIDTH = UIScreen.main.bounds.size.width
        static let SCREEN_HEIGHT = UIScreen.main.bounds.size.height
        static let SCREEN_MAX_LENGTH = max(ScreenSize.SCREEN_WIDTH, ScreenSize.SCREEN_HEIGHT)
        static let SCREEN_MIN_LENGTH = min(ScreenSize.SCREEN_WIDTH, ScreenSize.SCREEN_HEIGHT)
    }

    struct DeviceType
    {
        static let IS_IPHONE_4_OR_LESS =  UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.SCREEN_MAX_LENGTH < 568.0
        static let IS_IPHONE_5 = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.SCREEN_MAX_LENGTH == 568.0
        static let IS_IPHONE_6 = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.SCREEN_MAX_LENGTH >= 667.0
        static let IS_IPHONE_6P = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.SCREEN_MAX_LENGTH == 736.0
        static let IS_IPHONE_X = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.SCREEN_MAX_LENGTH == 812.0
        static let IS_IPAD      = UIDevice.current.userInterfaceIdiom == .pad && ScreenSize.SCREEN_MAX_LENGTH == 1024.0
        static let IS_IPAD_PRO  = UIDevice.current.userInterfaceIdiom == .pad && ScreenSize.SCREEN_MAX_LENGTH == 1366.0
    }

    struct VersionType{
        static let SYS_VERSION_FLOAT = (UIDevice.current.systemVersion as NSString).floatValue
        static let iOS7 = (VersionType.SYS_VERSION_FLOAT < 8.0 && VersionType.SYS_VERSION_FLOAT >= 7.0)
        static let iOS8 = (VersionType.SYS_VERSION_FLOAT >= 8.0 && VersionType.SYS_VERSION_FLOAT < 9.0)
        static let iOS9 = (VersionType.SYS_VERSION_FLOAT >= 9.0 && VersionType.SYS_VERSION_FLOAT < 10.0)
        static let iOS10 = (VersionType.SYS_VERSION_FLOAT >= 9.0 && VersionType.SYS_VERSION_FLOAT < 11.0)
    }
}

这是一个Swift版本的yasirmturk宏。希望它能帮助一些人

// MARK: System versionning

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

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

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

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

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

let kIsIOS7: Bool = SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO("7")
let kIsIOS7_1: Bool = SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO("7.1")
let kIsIOS8: Bool = SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO("8")
let kIsIOS9: Bool = SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO("9")