Load/Deserialize faster Json data to C# object

Question

In my code I use Newtonsoft.Json :

MyCSharpTargetClass foo = JsonConvert.DeserializeObject<MyCSharpTargetClass>(json_string);

The content of the json_string is constant (loaded from a file that never changes).

The functionality is fine but the deserializing process is slow at execution.

My question: is there a way to pre-calculate the object, or to put it in a constant*, or whatever to speed up the execution ?

Note: Actually I didn't manage to put it a constant the result of JsonConvert.DeserializeObject<...>(), but I'm new to C#, so I should have missed something.

Thanks for your help

[EDIT] Solution : Force the Newtonsoft assembly to be loaded at the start of the application.

Answer 1

You do it the same way you would any other object: make it a private member variable, whose value is computed exactly once:

private static readonly MyCSharpTargetClass foo = JsonConvert.DeserializeObject<MyCSharpTargetClass>(json_string);

Or do it in the constructor:

private readonly MyCSharpTargetClass foo;

public MyObject()
{
    foo = JsonConvert.DeserializeObject<MyCSharpTargetClass>(json_string);
}

That way the work to deserialize the string is done exactly once.

Answer 2

There's actualy not a lot of thinks you can do to speed this up.

1. Using ignore attribute, so this fields will not be added. Use this for some properties or calcualatable properties/fields, which can be recalculated later. Hope this link helps :

   https://msdn.microsoft.com/en-us/library/system.runtime.serialization.ignoredatamemberattribute.aspx

2. Using threads to read/write your objects, if you can customize your data into many files and serialize/deserialize in threads.

3. Deserialization JSON algorithms requires to read whole file about 3 times. For better perfomance you can use YAML. Simple as XML/JSON, but with much better perfomance, since it reads file only 1 time.
4. Using shorter DataMember names to fields [DataMember(Name = "id")] public int MyObjectForSomethink{get;set;}