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.netserializationjson.net

Can Json.NET serialize / deserialize to / from a stream?

I have heard that Json.NET is faster than DataContractJsonSerializer, and wanted to give it a try...

But I couldn't find any methods on JsonConvert that take a stream rather than a string.

For deserializing a file containing JSON on WinPhone, for example, I use the following code to read the file contents into a string, and then deserialize into JSON. It appears to be about 4 times slower in my (very ad-hoc) testing than using DataContractJsonSerializer to deserialize straight from the stream... 

// DCJS
DataContractJsonSerializer dc = new DataContractJsonSerializer(typeof(Constants));
Constants constants = (Constants)dc.ReadObject(stream);

// JSON.NET
string json = new StreamReader(stream).ReadToEnd();
Constants constants = JsonConvert.DeserializeObject<Constants>(json);

Am I doing it wrong?

Solution

  • UPDATE: This no longer works in the current version, see below for correct answer (no need to vote down, this is correct on older versions).

    Use the JsonTextReader class with a StreamReader or use the JsonSerializer overload that takes a StreamReader directly:

    var serializer = new JsonSerializer();
serializer.Deserialize(streamReader);