以前用UIScreen 的大小来判断设备类型，现在有了iphone6 和 iphone6 plus， 这种方法不能用了。因为当程序不提供相应的启动图片时，系统会把程序运行在320*568的size下，并把程序界面等比扩大，这样UIScreen 的大小就不能反映真实设备的分辨率了！见下面的截图
用以下方法解决，注意加头文件
#include "sys/sysctl.h"
+ (NSString*)getMachineName{ size_t size; sysctlbyname("hw.machine", NULL, &size, NULL, 0); char *name = malloc(size); sysctlbyname("hw.machine", name, &size, NULL, 0); NSString *platform = [NSString stringWithCString:name encoding:NSUTF8StringEncoding]; free(name); if ([platform isEqualToString:@"iPhone1,1"]) return @"iPhone 2G (A1203)"; if ([platform isEqualToString:@"iPhone1,2"]) return @"iPhone 3G (A1241/A1324)"; if ([platform isEqualToString:@"iPhone2,1"]) return @"iPhone 3GS (A1303/A1325)"; if ([platform isEqualToString:@"iPhone3,1"]) return @"iPhone 4 (A1332)"; if ([platform isEqualToString:@"iPhone3,2"]) return @"iPhone 4 (A1332)"; if ([platform isEqualToString:@"iPhone3,3"]) return @"iPhone 4 (A1349)"; if ([platform isEqualToString:@"iPhone4,1"]) return @"iPhone 4S (A1387/A1431)"; if ([platform isEqualToString:@"iPhone5,1"]) return @"iPhone 5 (A1428)"; if ([platform isEqualToString:@"iPhone5,2"]) return @"iPhone 5 (A1429/A1442)"; if ([platform isEqualToString:@"iPhone5,3"]) return @"iPhone 5c (A1456/A1532)"; if ([platform isEqualToString:@"iPhone5,4"]) return @"iPhone 5c (A1507/A1516/A1526/A1529)"; if ([platform isEqualToString:@"iPhone6,1"]) return @"iPhone 5s (A1453/A1533)"; if ([platform isEqualToString:@"iPhone6,2"]) return @"iPhone 5s (A1457/A1518/A1528/A1530)"; if ([platform isEqualToString:@"iPhone7,1"]) return @"iPhone 6 Plus (A1522/A1524)"; if ([platform isEqualToString:@"iPhone7,2"]) return @"iPhone 6 (A1549/A1586)"; if ([platform isEqualToString:@"iPod1,1"]) return @"iPod Touch 1G (A1213)"; if ([platform isEqualToString:@"iPod2,1"]) return @"iPod Touch 2G (A1288)"; if ([platform isEqualToString:@"iPod3,1"]) return @"iPod Touch 3G (A1318)"; if ([platform isEqualToString:@"iPod4,1"]) return @"iPod Touch 4G (A1367)"; if ([platform isEqualToString:@"iPod5,1"]) return @"iPod Touch 5G (A1421/A1509)"; if ([platform isEqualToString:@"iPad1,1"]) return @"iPad 1G (A1219/A1337)"; if ([platform isEqualToString:@"iPad2,1"]) return @"iPad 2 (A1395)"; if ([platform isEqualToString:@"iPad2,2"]) return @"iPad 2 (A1396)"; if ([platform isEqualToString:@"iPad2,3"]) return @"iPad 2 (A1397)"; if ([platform isEqualToString:@"iPad2,4"]) return @"iPad 2 (A1395+New Chip)"; if ([platform isEqualToString:@"iPad2,5"]) return @"iPad Mini 1G (A1432)"; if ([platform isEqualToString:@"iPad2,6"]) return @"iPad Mini 1G (A1454)"; if ([platform isEqualToString:@"iPad2,7"]) return @"iPad Mini 1G (A1455)"; if ([platform isEqualToString:@"iPad3,1"]) return @"iPad 3 (A1416)"; if ([platform isEqualToString:@"iPad3,2"]) return @"iPad 3 (A1403)"; if ([platform isEqualToString:@"iPad3,3"]) return @"iPad 3 (A1430)"; if ([platform isEqualToString:@"iPad3,4"]) return @"iPad 4 (A1458)"; if ([platform isEqualToString:@"iPad3,5"]) return @"iPad 4 (A1459)"; if ([platform isEqualToString:@"iPad3,6"]) return @"iPad 4 (A1460)"; if ([platform isEqualToString:@"iPad4,1"]) return @"iPad Air (A1474)"; if ([platform isEqualToString:@"iPad4,2"]) return @"iPad Air (A1475)"; if ([platform isEqualToString:@"iPad4,3"]) return @"iPad Air (A1476)"; if ([platform isEqualToString:@"iPad4,4"]) return @"iPad Mini 2G (A1489)"; if ([platform isEqualToString:@"iPad4,5"]) return @"iPad Mini 2G (A1490)"; if ([platform isEqualToString:@"iPad4,6"]) return @"iPad Mini 2G (A1491)"; if ([platform isEqualToString:@"i386"]) return @"iPhone Simulator"; if ([platform isEqualToString:@"x86_64"]) return @"iPhone Simulator"; return platform; }