只是为了结合@sickp的答案和下面来自@n13的评论，我把它做成了一个UIScreen类别，这似乎工作得很好。检查在您第一次调用它时完成，然后为以后的调用保存。

@interface UIScreen (RetinaCheck)
+ (BOOL)retinaScreen;
@end

static BOOL isRetinaScreen = NO;
static BOOL didRetinaCheck = NO;

@implementation UIScreen (RetinaCheck)
+ (BOOL)retinaScreen
{
    if (!didRetinaCheck) {
        isRetinaScreen = ([[self mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] &&
                          ([self mainScreen].scale == 2.0));
        didRetinaCheck = YES;
    }
    return isRetinaScreen;
}
@end

可能对某人有用。

+(BOOL)iPhoneRetina{
    return ([[UIScreen mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] && ([UIScreen mainScreen].scale == 2.0))?1:0;
}

SSToolkit有一个这样做的方法:

http://sstoolk.it/documentation/Categories/UIScreen (SSToolkitAdditions) . html

它的用法如下:

[[UIScreen mainScreen] isRetinaDisplay];

这个代码片段……

    int d = 0; // standard display
if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)] && [[UIScreen mainScreen] scale] == 2.0) {
    d = 1; // is retina display
}

if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
    d += 2;
}

将返回…… 0为标准分辨率iPhone/iPod touch， 1为retina iPhone， 2用于标准分辨率的iPad， 3视网膜iPad。

只是为了结合@sickp的答案和下面来自@n13的评论，我把它做成了一个UIScreen类别，这似乎工作得很好。检查在您第一次调用它时完成，然后为以后的调用保存。

@interface UIScreen (RetinaCheck)
+ (BOOL)retinaScreen;
@end

static BOOL isRetinaScreen = NO;
static BOOL didRetinaCheck = NO;

@implementation UIScreen (RetinaCheck)
+ (BOOL)retinaScreen
{
    if (!didRetinaCheck) {
        isRetinaScreen = ([[self mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] &&
                          ([self mainScreen].scale == 2.0));
        didRetinaCheck = YES;
    }
    return isRetinaScreen;
}
@end

可能对某人有用。

这是对Matt MC的回答的重复。只是UIScreen上的一个类别。

#import "UIScreen+Util.h"

@implementation UIScreen (Util)

+ (BOOL) isRetinaDisplay {
    static BOOL retina = NO;
    static BOOL alreadyChecked = NO;
    if (!alreadyChecked) {
        UIScreen *mainScreen = self.mainScreen;
        if (mainScreen) {
            retina = mainScreen.scale > 1.0;
            alreadyChecked = YES;
        }
    }
    return retina;
}

@end