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
作为yasimturks解决方案的一种变体,我定义了一个函数和一些枚举值,而不是五个宏。我觉得它更优雅,但那是个人品味的问题。
用法:
if (systemVersion(LessThan, @"5.0")) ...
. h文件:
typedef enum {
LessThan,
LessOrEqual,
Equal,
GreaterOrEqual,
GreaterThan,
NotEqual
} Comparison;
BOOL systemVersion(Comparison test, NSString* version);
m文件:
BOOL systemVersion(Comparison test, NSString* version) {
NSComparisonResult result = [[[UIDevice currentDevice] systemVersion] compare: version options: NSNumericSearch];
switch (test) {
case LessThan: return result == NSOrderedAscending;
case LessOrEqual: return result != NSOrderedDescending;
case Equal: return result == NSOrderedSame;
case GreaterOrEqual: return result != NSOrderedAscending;
case GreaterThan: return result == NSOrderedDescending;
case NotEqual: return result != NSOrderedSame;
}
}
你应该在名称中添加应用程序的前缀,尤其是比较类型。
其他回答
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;
}
+(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;
}
}
仅用于检索OS版本字符串值:
[[UIDevice currentDevice] systemVersion]
开始Xcode 9,在Objective-C中:
if (@available(iOS 11, *)) {
// iOS 11 (or newer) ObjC code
} else {
// iOS 10 or older code
}
开始Xcode 7,在Swift中:
if #available(iOS 11, *) {
// iOS 11 (or newer) Swift code
} else {
// iOS 10 or older code
}
对于版本,您可以指定MAJOR、MINOR或PATCH(参见http://semver.org/的定义)。例子:
iOS 11和iOS 11.0是相同的最小版本 iOS 10, iOS 10.3, iOS 10.3.1是不同的最小版本
您可以为这些系统中的任何一个输入值:
iOS, macOS, watchOS, tvOS
来自我的一个豆荚的真实案例:
if #available(iOS 10.0, tvOS 10.0, *) {
// iOS 10+ and tvOS 10+ Swift code
} else {
// iOS 9 and tvOS 9 older code
}
文档
在主界面轻按“设置”>常规>关于。 设备的软件版本应该出现在这个屏幕上。 检查版本号是否大于3.1.3。