I serialize an array of large objects to a json http response stream. Now I want to deserialize these objects from the stream one at a time. Are there any c# libraries that will let me do this? I've looked at json.net but it seems I'd have to deserialize the complete array of objects at once.
[{large json object},{large json object}.....]
Clarification: I want to read one json object from the stream at a time and deserialize it.
In order to read the JSON incrementally, you'll need to use a JsonTextReader in combination with a StreamReader. But, you don't necessarily have to read all the JSON manually from the reader. You should be able to leverage the Linq-To-JSON API to load each large object from the reader so that you can work with it more easily.
For a simple example, say I had a JSON file that looked like this:
[
{
"name": "foo",
"id": 1
},
{
"name": "bar",
"id": 2
},
{
"name": "baz",
"id": 3
}
]
Code to read it incrementally from the file might look something like the following. (In your case you would replace the FileStream with your response stream.)
using (FileStream fs = new FileStream(@"C:\temp\data.json", FileMode.Open, FileAccess.Read))
using (StreamReader sr = new StreamReader(fs))
using (JsonTextReader reader = new JsonTextReader(sr))
{
while (reader.Read())
{
if (reader.TokenType == JsonToken.StartObject)
{
// Load each object from the stream and do something with it
JObject obj = JObject.Load(reader);
Console.WriteLine(obj["id"] + " - " + obj["name"]);
}
}
}
Output of the above would look like this:
1 - foo
2 - bar
3 - baz
With Cinchoo ETL - an open source library, you can parse large JSON efficiently with low memory footprint. Since the objects are constructed and returned in a stream based pull model
using (var p = new ChoJSONReader(** YOUR JSON FILE **))
{
foreach (var rec in p)
{
Console.WriteLine($"Name: {rec.name}, Id: {rec.id}");
}
}
For more information, please visit codeproject article.
Hope it helps.