报错信息为：variable support issue in mutations: "Variable '$input' is invalid. Unable to parse input as a 'heroInput' type. Did you provide a List or Scalar value accidentally?"
原因为 Controller Post 参数解析 GraphQLRequest 不是使用 GraphQLSerializer 解析，InputObjectGraphType 类型参数没有解析为 IDictionary<string, object> （GraphQL.net 官方 Examples 太久没更新）
1 public async Task<HttpResponseMessage> PostAsync(HttpRequestMessage request, GraphQLRequest query)
使用 GraphQLSerializer 解析后正常
var query = new GraphQLSerializer().Deserialize<GraphQLRequest>(requestJson);