NSData NSDate NSString NSArray NSDictionary 相互转化

1. //    NSData  NSDate NSString NSArray NSDictionary json
2. NSString *string = @"hello word";
3. NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
4. NSArray *array = [NSArray arrayWithObjects:@"1",@"2",@"3",nil];
5. NSString *dateString = @"19891123";
6. NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:
7. @"hello", @"word",
8. @"chen", @"lu",
9. @"jin", @"mei",
10. @"cerastes", @"hehe",nil];
11. //    NSString to NSData
12. NSData *string2data = [string dataUsingEncoding:NSUTF8StringEncoding];
13. NSLog(@"%@",string2data);
14. //    NSData to NSString
15. NSString *data2String = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];
16. NSLog(@"dataString = %@",data2String);
17. //    NSArray to NSData
18. NSData *arry2data = [NSKeyedArchiver archivedDataWithRootObject:array];
19. //    NSData to NSArray
20. NSArray *data2arry = [NSKeyedUnarchiver unarchiveObjectWithData:arry2data];
21. NSLog(@"%@  /n %@",arry2data,data2arry);
22. //    NSString to NSDate
23. NSDate *string2date = [self convertDateFromString:dateString withFormattre:@"yyyyMMdd"];
24. NSLog(@"date = %@",string2date);
25. //    NSDate to NSString
26. NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
27. [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
28. NSString *date2string = [dateFormatter stringFromDate:[NSDate date]];
29. NSLog(@"%@", date2string);
30. //   NSArray to NSString
31. NSString *arry2String = [array componentsJoinedByString:@" "];
32. NSLog(@"string = %@",arry2String);
33. //    NSString to NSArray
34. NSArray *string2Arry = [arry2String componentsSeparatedByString:@" "];
35. NSLog(@" %@",string2Arry);
36. //    NSDictionary to NSData:
37. NSMutableData *dic2data = [[NSMutableData alloc] init];
38. NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:dic2data];
39. [archiver encodeObject:dic forKey:@"Some Key Value"];
40. [archiver finishEncoding];
41. NSLog(@"%@",dic2data);
42. //    NSData to NSDictionary
43. NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:dic2data];
44. NSDictionary *data2dic = [unarchiver decodeObjectForKey:@"Some Key Value"];
45. [unarchiver finishDecoding];
46. NSLog(@"%@",data2dic);
47. //    NSDictionary to NSString
48. NSString *dic2string=[dic JSONRepresentation]; //这个方法是SBJson类库里的，需要导入SBJson.h
49. NSLog(@"%@",dic2string);
50. //    NSString to NSDictionary
51. NSError *error = nil;
52. NSDictionary *string2dic = [NSJSONSerialization JSONObjectWithData: [dic2string dataUsingEncoding:NSUTF8StringEncoding]
53. options: NSJSONReadingMutableContainers
54. error: &error];
55. NSLog(@"%@",string2dic);