1 #import "HMViewController.h"
 2 #import "NSString+Hash.h"
 3
 4 #define Salt @"fsdhjkfhjksdhjkfjhkd546783765"
 5
 6 @interface HMViewController ()
 7
 8 @end
 9
10 @implementation HMViewController
11
12 - (void)viewDidLoad
13 {
14     [super viewDidLoad];
15
16     [self digest:@"123"]; //
17     [self digest:@"abc"];
18     [self digest:@"456"];
19 }
20
21 /**
22  *  直接用MD5加密
23  */
24 - (NSString *)digest:(NSString *)str
25 {
26     NSString *anwen = [str md5String];
27     NSLog(@"%@ - %@", str, anwen);
28     return anwen;
29 }
30
31 /**
32  *  加盐
33  */
34 - (NSString *)digest2:(NSString *)str
35 {
36     str = [str stringByAppendingString:Salt];
37
38     NSString *anwen = [str md5String];
39     NSLog(@"%@ - %@", str, anwen);
40     return anwen;
41 }
42
43 /**
44  *  多次MD5
45  */
46 - (NSString *)digest3:(NSString *)str
47 {
48     NSString *anwen = [str md5String];
49
50     anwen = [anwen md5String];
51
52     NSLog(@"%@ - %@", str, anwen);
53     return anwen;
54 }
55
56 /**
57  *  先加密, 后乱序
58  */
59 - (NSString *)digest4:(NSString *)str
60 {
61     NSString *anwen = [str md5String];
62
63     // 注册:  123 ----  2CB962AC59075B964B07152D234B7020
64
65     // 登录: 123 --- 202CB962AC59075B964B07152D234B70
66
67     NSString *header = [anwen substringToIndex:2];
68     NSString *footer = [anwen substringFromIndex:2];
69     anwen = [footer stringByAppendingString:header];
70
71     NSLog(@"%@ - %@", str, anwen);
72     return anwen;
73 }
74 @end