这对我很有效

if((UIScreen .mainScreen().scale) < 2.0)
{
    NSLog("no retina");
}
else
{
    NSLog("retina");
}

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。

这对我很有效

if((UIScreen .mainScreen().scale) < 2.0)
{
    NSLog("no retina");
}
else
{
    NSLog("retina");
}

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];

这是一个方便的快速扩展:

Swift v5更新:

extension UIScreen {

    public var isRetina: Bool {
        guard let scale = screenScale else {
            return false
        }
        return scale >= 2.0
    }

    public var isRetinaHD: Bool {
        guard let scale = screenScale else {
            return false
        }
        return scale >= 3.0
    }

    private var screenScale: CGFloat? {
        guard UIScreen.main.responds(to: #selector(getter: scale)) else {
            return nil
        }
        return UIScreen.main.scale
    }
}

用法:

if UIScreen.main.isRetina {
    // Your code
}

原:

extension UIScreen { 
public func isRetina() -> Bool {
    return screenScale() >= 2.0
}

public func isRetinaHD() -> Bool {
    return screenScale() >= 3.0
}

private func screenScale() -> CGFloat? {
    if UIScreen.mainScreen().respondsToSelector(Selector("scale")) {
        return UIScreen.mainScreen().scale
    }
    return nil
    }
}

用法:

if UIScreen.mainScreen().isRetina() {
 // your code
        }

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