您的示例是序列化字符串.如果您将输入转换为对象然后反序列化，它将起作用:

Your example is serialising a string. If you convert your input to an object then deserialise, it will work:

    static void Main(string[] args)
    {
        var myJsonInput = @"{'Id':'123','Name':'abc'}";
        var jsonSerializerSettings = new JsonSerializerSettings
        {
            ContractResolver = new CamelCasePropertyNamesContractResolver()
        };
        var interimObject = JsonConvert.DeserializeObject<ExpandoObject>(myJsonInput);
        var myJsonOutput = JsonConvert.SerializeObject(interimObject, jsonSerializerSettings);

        Console.Write(myJsonOutput);
        Console.ReadKey();
    }