1 //字典转NSData:
 2 +(NSData *)returnDataWithDictionary:(NSDictionary*)dict
 3 {
 4     NSMutableData *data =http://www.mamicode.com/ [[NSMutableData alloc]init];
 5     NSKeyedArchiver* archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:data];
 6     [archiver encodeObject:dict forKey:@"talkData"];
 7     [archiver finishEncoding];
 8     return data;
 9 }
10 
11 //NSData 转字典:
12 // NSData转dictonary
13 +(NSDictionary*)returnDictionaryWithDataPath:(NSData*)data
14 {
15     //  NSData* data = http://www.mamicode.com/[[NSMutableData alloc]initWithContentsOfFile:path]; 拿路径文件
16     NSKeyedUnarchiver* unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:data];
17     NSDictionary* myDictionary = [unarchiver decodeObjectForKey:@"talkData"];
18     [unarchiver finishDecoding];
19     return myDictionary;
20 }