Updated on Kisan Patel
Install the Microsoft.AspNetCore.Mvc.NewtonsoftJson package.
Update Startup.ConfigureServices to call AddNewtonsoftJson.
services.AddSignalR()
.AddNewtonsoftJsonProtocol(
options =>
options.PayloadSerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver()
);
Source:
https://stackoverflow.com/questions/37832165/signalr-net-core-camelcase-json-contract-resolver
https://docs.microsoft.com/en-us/aspnet/core/migration/22-to-30?view=aspnetcore-3.0&tabs=visual-studio