获取设备类型及信息

    一般只对设备的iPhone或iPad设备进行判断，那么只需使用

UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad或者UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone即可。

如果要求较高可以用

[[UIDevice currentDevice] systemName];
[[UIDevice currentDevice] systemVersion]; //ios version
[[UIDevice currentDevice] uniqueIdentifier]; //ios5以后弃用的方法。
[[UIDevice currentDevice] model]; // 设备类型 iPad or iphone
[[UIDevice currentDevice] name]; // 机子主人取的名字




    上面的方法很好用，但是有时需要判断具体的设备类型，如iPad1，iPad2，iPhone4，iPhone5等等，那么只能使用以下的这个方法

+ (NSString*)deviceString

{

    // 需要#import "sys/utsname.h"

    struct utsname systemInfo;

    uname(&systemInfo);

    NSString *deviceString = [NSString stringWithCString:systemInfo.machine encoding:NSUTF8StringEncoding];




    if ([deviceString isEqualToString:@"iPhone1,1"])    return @"iPhone 1G";

    if ([deviceString isEqualToString:@"iPhone1,2"])    return @"iPhone 3G";

    if ([deviceString isEqualToString:@"iPhone2,1"])    return @"iPhone 3GS";

    if ([deviceString isEqualToString:@"iPhone3,1"])    return @"iPhone 4";

    if ([deviceString isEqualToString:@"iPhone4,1"])    return @"iPhone 4S";

    if ([deviceString isEqualToString:@"iPhone5,2"])    return @"iPhone 5";

    if ([deviceString isEqualToString:@"iPhone3,2"])    return @"Verizon iPhone 4";

    if ([deviceString isEqualToString:@"iPod1,1"])      return @"iPod Touch 1G";

    if ([deviceString isEqualToString:@"iPod2,1"])      return @"iPod Touch 2G";

    if ([deviceString isEqualToString:@"iPod3,1"])      return @"iPod Touch 3G";

    if ([deviceString isEqualToString:@"iPod4,1"])      return @"iPod Touch 4G";

    if ([deviceString isEqualToString:@"iPad1,1"])      return @"iPad";

    if ([deviceString isEqualToString:@"iPad2,1"])      return @"iPad 2 (WiFi)";

    if ([deviceString isEqualToString:@"iPad2,2"])      return @"iPad 2 (GSM)";

    if ([deviceString isEqualToString:@"iPad2,3"])      return @"iPad 2 (CDMA)";

    if ([deviceString isEqualToString:@"i386"])         return @"Simulator";

    if ([deviceString isEqualToString:@"x86_64"])       return @"Simulator";

    NSLog(@"NOTE: Unknown device type: %@", deviceString);

    return deviceString;

}