How can I custom a .Net Json serialize settings to handle json key fields? [duplicate]

Here is a data contract

class A
{
    public string Name{get;set;}
}

We are going to use var obj = JsonConvert.DeserializeObject<A>(jsongString) to deserialize the json string into an object. But the json looks like:

{
    "#Name#": "A"
}

Any change or inheritage are not allowed to class A in A.cs file, such as add attribute [JSONProperty(PropertyName="#Name#")] to property. Is it possible to deserialize the string with a customed deserialize settings, what I want is just like:

var deserializeSetting = new CustomedSettings();
var obj = JsonConvert.DeserializeObject<A>(jsonString, deserializeSetting);