IOS 数据转换

• NSDictionary to NSData

    NSMutableDictionary *mDic = [[NSMutableDictionary alloc] initWithCapacity:1];
    [mDic setValue:@"test1" forKey:@"test1"];
    [mDic setValue:@"test2" forKey:@"test2"];
    [mDic setValue:@"test3" forKey:@"test3"];
    [mDic setValue:@"test4" forKey:@"test4"];
    [mDic setValue:@"test5" forKey:@"test5"];
    
    NSLog(@"mdic = %@", mDic);
    
    NSMutableData *mData = [[NSMutableData alloc] init];
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:mData];
    [archiver encodeObject:mDic forKey:@"mutDic"];
    [archiver finishEncoding];
    NSLog(@"mdata = %@", mData);

• NSData to NSString

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

• NSString to NSData

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

• NSData to NSDictionary