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
我总是把它们保存在Constants.h文件中:
#define IS_IPHONE5 (([[UIScreen mainScreen] bounds].size.height-568)?NO:YES)
#define IS_OS_5_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 5.0)
#define IS_OS_6_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 6.0)
#define IS_OS_7_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)
#define IS_OS_8_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
#define _kisiOS7 ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0)
if (_kisiOS7) {
NSLog(@"iOS7 or greater")
}
else {
NSLog(@"Less than iOS7");
}
有7.0或6.0.3这样的版本,所以我们可以简单地将版本转换为数字进行比较。如果版本类似于7.0,只需追加另一个”。0”,然后取它的数值。
int version;
NSString* iosVersion=[[UIDevice currentDevice] systemVersion];
NSArray* components=[iosVersion componentsSeparatedByString:@"."];
if ([components count]==2) {
iosVersion=[NSString stringWithFormat:@"%@.0",iosVersion];
}
iosVersion=[iosVersion stringByReplacingOccurrencesOfString:@"." withString:@""];
version=[iosVersion integerValue];
为0
if (version==600) {
// Do something
}
为7.0
if (version==700) {
// Do something
}
一个在obj - c++ 11中更通用的版本(你可能会用NSString/C函数替换其中的一些东西,但这不是那么冗长。这给了你两种机制。splitSystemVersion为你提供了一个包含所有部分的数组,如果你只是想打开主版本(例如switch([self splitSystemVersion][0]) {case 4: break;案例5:断裂;})。
#include <boost/lexical_cast.hpp>
- (std::vector<int>) splitSystemVersion {
std::string version = [[[UIDevice currentDevice] systemVersion] UTF8String];
std::vector<int> versions;
auto i = version.begin();
while (i != version.end()) {
auto nextIllegalChar = std::find_if(i, version.end(), [] (char c) -> bool { return !isdigit(c); } );
std::string versionPart(i, nextIllegalChar);
i = std::find_if(nextIllegalChar, version.end(), isdigit);
versions.push_back(boost::lexical_cast<int>(versionPart));
}
return versions;
}
/** Losslessly parse system version into a number
* @return <0>: the version as a number,
* @return <1>: how many numeric parts went into the composed number. e.g.
* X.Y.Z = 3. You need this to know how to compare again <0>
*/
- (std::tuple<int, int>) parseSystemVersion {
std::string version = [[[UIDevice currentDevice] systemVersion] UTF8String];
int versionAsNumber = 0;
int nParts = 0;
auto i = version.begin();
while (i != version.end()) {
auto nextIllegalChar = std::find_if(i, version.end(), [] (char c) -> bool { return !isdigit(c); } );
std::string versionPart(i, nextIllegalChar);
i = std::find_if(nextIllegalChar, version.end(), isdigit);
int part = (boost::lexical_cast<int>(versionPart));
versionAsNumber = versionAsNumber * 100 + part;
nParts ++;
}
return {versionAsNumber, nParts};
}
/** Assume that the system version will not go beyond X.Y.Z.W format.
* @return The version string.
*/
- (int) parseSystemVersionAlt {
std::string version = [[[UIDevice currentDevice] systemVersion] UTF8String];
int versionAsNumber = 0;
int nParts = 0;
auto i = version.begin();
while (i != version.end() && nParts < 4) {
auto nextIllegalChar = std::find_if(i, version.end(), [] (char c) -> bool { return !isdigit(c); } );
std::string versionPart(i, nextIllegalChar);
i = std::find_if(nextIllegalChar, version.end(), isdigit);
int part = (boost::lexical_cast<int>(versionPart));
versionAsNumber = versionAsNumber * 100 + part;
nParts ++;
}
// don't forget to pad as systemVersion may have less parts (i.e. X.Y).
for (; nParts < 4; nParts++) {
versionAsNumber *= 100;
}
return versionAsNumber;
}
/*
* 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")) {
...
}