问题
I have a WebAPI in .NET Core 2.1 e I have using the RestSharp to access the API. When I send a request (POST), I always receive the below message in the response:
{System.Net.WebException: Error getting response stream (ReadAsync): ReceiveFailure Value cannot be null.Parameter name: src ---> System.ArgumentNullException: Value cannot be null.Parameter name: src at System.Net.HttpWebRequest+d__2411[T].MoveNext () [0x000ba] in <b78695579ed9422b8bc80218eeda782c>:0 --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in <43dbbdc147f2482093d8409abb04c233>:0 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in <43dbbdc147f2482093d8409abb04c233>:0 at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in <43dbbdc147f2482093d8409abb04c233>:0 at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in <43dbbdc147f2482093d8409abb04c233>:0 at System.Net.WebResponseStream+d__48.MoveNext () [0x00253] in :0 --- End of inner exception stack trace --- at System.Net.WebConnectionStream.Read (System.Byte[] buffer, System.Int32 offset, System.Int32 count) [0x00077] in :0 at RestSharp.Extensions.MiscExtensions.ReadAsBytes (System.IO.Stream input) [0x0001f] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 at RestSharp.Http.ProcessResponseStream (System.IO.Stream webResponseStream, RestSharp.HttpResponse response) [0x0000e] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 at RestSharp.Http.ExtractResponseData (RestSharp.HttpResponse response, System.Net.HttpWebResponse webResponse) [0x0004c] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 at RestSharp.Http+<>c__DisplayClass20_0.b__0 (System.Net.HttpWebResponse webResponse) [0x00001] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 at RestSharp.Http.GetRawResponseAsync (System.IAsyncResult result, System.Action1[T] callback) [0x00050] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 at RestSharp.Http.ResponseCallback (System.IAsyncResult result, System.Action1[T] callback) [0x0005a] in <4b0c1fc6e5a94482990701acc6dec8b3>:0 }
The previous version of my service (.NET Framework 4.7) was working, but my new version is not. I checked the URL and that is okay, and the service is working on Swagger and Postman, and I have the SSL certificate configured on the server, but in the App I continue receiving such message.
My service is hosted on Microsoft Azure.
Does anyone any idea to help me?
回答1:
Ok. I resolved.
I had the below code:
IRestRequest request = new RestRequest(method, Method.POST);
request.AddParameter("SampleKey", "SampleValue");
I don´t know why it was working with a .Net Framework WebApi, but is not working with a .Net Core WebApi.
I could resolve using the below code:
IRestRequest request = new RestRequest(method, Method.POST);
request.AddJsonBody(objBody);
With the new method, the RestSharp is responsible to serialize my object.
It's working right now.
来源：https://stackoverflow.com/questions/52030886/xamarin-restsharp-net-core-web-api-value-cannot-be-null-parameter-name-s