如何在Ruby中将字节数组转换为JSON字符串

Question

What I am trying to achieve:

1. Convert a Dictionary to NSData which contains normal text as well as an image:

    let payload: Dictionary<String, AnyObject> = [ "some_item": "some_value", "img": UIImagePNGRepresentation(img)! ] let data: NSData = NSKeyedArchiver.archivedDataWithRootObject(payload) 

2. Send this data to the server using WebSocket writeData

3. Parse the array of bytes to get a JSON string and save the image and send back some response.

I am using Rails4 as the backend and I have tried pack but it doesn't work. I am not sure if this is doable or not.

I know Base64 encoding will work instead of byte data, but it's a bit slower than what I would prefer.

Answer 1

First you need to stop using NSKeyedArchiver and instead use NSJSONSerialization .Tl his will generate actual JSON data for you that you should be able to unpack easily on the server.

When using an image you either:

1. don't use JSON with it
2. convert the image data into base64 and create the JSON including that text
3. use multi-part form upload with a section for the image and another for the rest of the JSON