Convert nsdictionary to nsdata

Question

have an app that can take a picture and then upload to a server. encoding it to base 64 and pass it thru a XMLRPC to my php server.

i want to take the NSDictionary info

Answer 1

Three options occur to me on this, two mentioned in other answers NSKeyedArchiver and PropertyList, there is also NSJSONSerialization that gave me the most compact data in a simple test.

NSDictionary *dictionary = @{@"message":@"Message from a cool guy", @"flag":@1};
NSData *prettyJson = [NSJSONSerialization dataWithJSONObject:dictionary options:NSJSONWritingPrettyPrinted error:nil];
NSData *compactJson = [NSJSONSerialization dataWithJSONObject:dictionary options:0 error:nil];
NSData *plist = [NSPropertyListSerialization dataWithPropertyList:dictionary
                                                           format:NSPropertyListBinaryFormat_v1_0
                                                          options:0
                                                            error:NULL];
NSData *archived = [NSKeyedArchiver archivedDataWithRootObject:dictionary];`

Size results for the different approaches smallest to largest

• compactJson 46 bytes
• prettyJson 57 bytes
• plist 91 bytes
• archived 316 bytes