我想检查设备的iOS版本是否大于3.1.3 我尝试了以下方法:
[[UIDevice currentDevice].systemVersion floatValue]
但是不管用,我只想要一个:
if (version > 3.1.3) { }
我怎样才能做到这一点呢?
我想检查设备的iOS版本是否大于3.1.3 我尝试了以下方法:
[[UIDevice currentDevice].systemVersion floatValue]
但是不管用,我只想要一个:
if (version > 3.1.3) { }
我怎样才能做到这一点呢?
当前回答
以下是一个简短的版本:
struct iOSVersion {
static let SYS_VERSION_FLOAT = (UIDevice.currentDevice().systemVersion as NSString).floatValue
static let iOS7 = (Version.SYS_VERSION_FLOAT < 8.0 && Version.SYS_VERSION_FLOAT >= 7.0)
static let iOS8 = (Version.SYS_VERSION_FLOAT >= 8.0 && Version.SYS_VERSION_FLOAT < 9.0)
static let iOS9 = (Version.SYS_VERSION_FLOAT >= 9.0 && Version.SYS_VERSION_FLOAT < 10.0)
}
用法:
if iOSVersion.iOS8 {
//Do iOS8 code here
}
其他回答
UIDevice + IOSVersion.h
@interface UIDevice (IOSVersion)
+ (BOOL)isCurrentIOSVersionEqualToVersion:(NSString *)iOSVersion;
+ (BOOL)isCurrentIOSVersionGreaterThanVersion:(NSString *)iOSVersion;
+ (BOOL)isCurrentIOSVersionGreaterThanOrEqualToVersion:(NSString *)iOSVersion;
+ (BOOL)isCurrentIOSVersionLessThanVersion:(NSString *)iOSVersion;
+ (BOOL)isCurrentIOSVersionLessThanOrEqualToVersion:(NSString *)iOSVersion
@end
UIDevice + IOSVersion.m
#import "UIDevice+IOSVersion.h"
@implementation UIDevice (IOSVersion)
+ (BOOL)isCurrentIOSVersionEqualToVersion:(NSString *)iOSVersion
{
return [[[UIDevice currentDevice] systemVersion] compare:iOSVersion options:NSNumericSearch] == NSOrderedSame;
}
+ (BOOL)isCurrentIOSVersionGreaterThanVersion:(NSString *)iOSVersion
{
return [[[UIDevice currentDevice] systemVersion] compare:iOSVersion options:NSNumericSearch] == NSOrderedDescending;
}
+ (BOOL)isCurrentIOSVersionGreaterThanOrEqualToVersion:(NSString *)iOSVersion
{
return [[[UIDevice currentDevice] systemVersion] compare:iOSVersion options:NSNumericSearch] != NSOrderedAscending;
}
+ (BOOL)isCurrentIOSVersionLessThanVersion:(NSString *)iOSVersion
{
return [[[UIDevice currentDevice] systemVersion] compare:iOSVersion options:NSNumericSearch] == NSOrderedAscending;
}
+ (BOOL)isCurrentIOSVersionLessThanOrEqualToVersion:(NSString *)iOSVersion
{
return [[[UIDevice currentDevice] systemVersion] compare:iOSVersion options:NSNumericSearch] != NSOrderedDescending;
}
@end
一般来说,最好是询问一个对象是否可以执行给定的选择器,而不是检查版本号来决定它是否必须存在。
当这不是一个选项,你需要在这里有点小心,因为[@"5.0"比较:@"5"选项:NSNumericSearch]返回nsordereddescent这可能不是有意的;我可能期待NSOrderedSame。这至少是一个理论上的问题,在我看来,这是一个值得防范的问题。
同样值得考虑的是,可能会出现无法合理比较的糟糕版本输入。苹果提供了三个预定义的常量NSOrderedAscending, NSOrderedSame和nsordereddescent,但我可以想到一个叫做NSOrderedUnordered的东西的使用,在我不能比较两个东西的情况下,我想返回一个值来指示这个。
更重要的是,苹果有一天会扩展他们的三个预定义常量以允许各种返回值,这是不可能的,这使得比较不明智。
考虑下面的代码。
typedef enum {kSKOrderedNotOrdered = -2, kSKOrderedAscending = -1, kSKOrderedSame = 0, kSKOrderedDescending = 1} SKComparisonResult;
@interface SKComparator : NSObject
+ (SKComparisonResult)comparePointSeparatedVersionNumber:(NSString *)vOne withPointSeparatedVersionNumber:(NSString *)vTwo;
@end
@implementation SKComparator
+ (SKComparisonResult)comparePointSeparatedVersionNumber:(NSString *)vOne withPointSeparatedVersionNumber:(NSString *)vTwo {
if (!vOne || !vTwo || [vOne length] < 1 || [vTwo length] < 1 || [vOne rangeOfString:@".."].location != NSNotFound ||
[vTwo rangeOfString:@".."].location != NSNotFound) {
return SKOrderedNotOrdered;
}
NSCharacterSet *numericalCharSet = [NSCharacterSet characterSetWithCharactersInString:@".0123456789"];
NSString *vOneTrimmed = [vOne stringByTrimmingCharactersInSet:numericalCharSet];
NSString *vTwoTrimmed = [vTwo stringByTrimmingCharactersInSet:numericalCharSet];
if ([vOneTrimmed length] > 0 || [vTwoTrimmed length] > 0) {
return SKOrderedNotOrdered;
}
NSArray *vOneArray = [vOne componentsSeparatedByString:@"."];
NSArray *vTwoArray = [vTwo componentsSeparatedByString:@"."];
for (NSUInteger i = 0; i < MIN([vOneArray count], [vTwoArray count]); i++) {
NSInteger vOneInt = [[vOneArray objectAtIndex:i] intValue];
NSInteger vTwoInt = [[vTwoArray objectAtIndex:i] intValue];
if (vOneInt > vTwoInt) {
return kSKOrderedDescending;
} else if (vOneInt < vTwoInt) {
return kSKOrderedAscending;
}
}
if ([vOneArray count] > [vTwoArray count]) {
for (NSUInteger i = [vTwoArray count]; i < [vOneArray count]; i++) {
if ([[vOneArray objectAtIndex:i] intValue] > 0) {
return kSKOrderedDescending;
}
}
} else if ([vOneArray count] < [vTwoArray count]) {
for (NSUInteger i = [vOneArray count]; i < [vTwoArray count]; i++) {
if ([[vTwoArray objectAtIndex:i] intValue] > 0) {
return kSKOrderedAscending;
}
}
}
return kSKOrderedSame;
}
@end
首选的方法
在Swift 2.0中,苹果使用更方便的语法添加了可用性检查(点击这里阅读更多)。现在你可以用更简洁的语法检查操作系统版本:
if #available(iOS 9, *) {
// Then we are on iOS 9
} else {
// iOS 8 or earlier
}
这是首选检查respondsToSelector等(什么是新的在Swift)。现在,如果你没有正确地保护你的代码,编译器总是会警告你。
斯威夫特2.0
iOS 8的新功能是NSProcessInfo,允许更好的语义版本检查。
在iOS 8及更高版本上部署
对于iOS 8.0或以上版本的最低部署目标,使用NSProcessInfo operatingSystemVersion或isOperatingSystemAtLeastVersion。
这将产生以下结果:
let minimumVersion = NSOperatingSystemVersion(majorVersion: 8, minorVersion: 1, patchVersion: 2)
if NSProcessInfo().isOperatingSystemAtLeastVersion(minimumVersion) {
//current version is >= (8.1.2)
} else {
//current version is < (8.1.2)
}
在iOS 7上部署
对于iOS 7.1或以下的最低部署目标,使用compare with NSStringCompareOptions。UIDevice systemVersion上的NumericSearch。
这将产生:
let minimumVersionString = "3.1.3"
let versionComparison = UIDevice.currentDevice().systemVersion.compare(minimumVersionString, options: .NumericSearch)
switch versionComparison {
case .OrderedSame, .OrderedDescending:
//current version is >= (3.1.3)
break
case .OrderedAscending:
//current version is < (3.1.3)
fallthrough
default:
break;
}
更多阅读请访问NSHipster。
/*
* System Versioning Preprocessor Macros
*/
#define SYSTEM_VERSION_EQUAL_TO(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedSame)
#define SYSTEM_VERSION_GREATER_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedDescending)
#define SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending)
#define SYSTEM_VERSION_LESS_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)
#define SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedDescending)
/*
* Usage
*/
if (SYSTEM_VERSION_LESS_THAN(@"4.0")) {
...
}
if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"3.1.1")) {
...
}
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)
}
}