IOS 数据转换

NSDictionary to NSData

 1   NSMutableDictionary *mDic = [[NSMutableDictionary alloc] initWithCapacity:1];
 2   [mDic setValue:@"test1" forKey:@"test1"];
 3   [mDic setValue:@"test2" forKey:@"test2"];
 4   [mDic setValue:@"test3" forKey:@"test3"];
 5   [mDic setValue:@"test4" forKey:@"test4"];
 6   [mDic setValue:@"test5" forKey:@"test5"];
 7   
 8   NSLog(@"mdic = %@", mDic);
 9   
10   NSMutableData *mData = [[NSMutableData alloc] init];
11   NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:mData];
12   [archiver encodeObject:mDic forKey:@"mutDic"];
13   [archiver finishEncoding];
14   NSLog(@"mdata = %@", mData);

NSData to NSString

1   NSMutableData *mData = [[NSMutableData alloc] init];
2   NSString *mStr = [[NSString alloc] initWithData:mData encoding:NSUTF8StringEncoding];
3   NSLog(@"mstr = %@", mStr);

NSString to NSData

1   NSString *mStr = [[NSString alloc] initWithData:mData encoding:NSUTF8StringEncoding];
2   NSLog(@"mstr = %@", mStr);
3   
4   NSData *data = [mStr dataUsingEncoding:NSUTF8StringEncoding];

NSData to NSDictionary