安装
GraphQL 7.0.0
GraphQL.SystemTextJson 7.0.0

HelloWorld

public class Program
    {
        public static async Task Main(string[] args)
        {
            var schema = Schema.For(@"
      type Query {
        hello: String
      }
    ");
            var json = await schema.ExecuteAsync(_ =>
            {
                _.Query = "{ hello }";
                _.Root = new { Hello = "Hello World!" };
            });

            Console.WriteLine(json);
        }
    }

客户端工具
altair_4.6.2_x64_win 类似postman

[参考]
​​​GraphQL.NET​​

留待后查，同时方便他人