WPF Report viewer handle error with exception "Object reference not set to an instance of an object"

[Aleksey]

Hello,

I'm  using Telerik Reporting version 15.0.21.326 and WPF report viewer with REST services. When my custom report source resolver return null or custom exception I have exception "Object reference not set to an instance of an object" with stack trace:

at Telerik.ReportViewer.Common.RestServiceProxyEngine.<>c.<GetParameters>b__14_0(JsonExceptionData ex)
at Telerik.Reporting.Services.HttpClient.HttpRequestHelper.PostJson[T](String request, HttpClient client, Object value, Func`2 getDefaultValue, IEnumerable`1 formatters)
at Telerik.Reporting.Services.HttpClient.GenericHttpClient.<>c__DisplayClass13_0`1.<PostJson>b__0(HttpClient client)
at Telerik.Reporting.Services.HttpClient.LocalLoginSession.MakeRequest[T](Func`2 action)
at Telerik.Reporting.Services.HttpClient.GenericHttpClient.PostJson[TResult](String action, Object value, Func`2 getDefaultValue, IEnumerable`1 formatters)
at Telerik.Reporting.Services.HttpClient.GenericHttpClient.PostJson[TResult](String action, Object value, Func`2 getDefaultValue, Boolean ignoreSerializableAttribute)
at Telerik.ReportViewer.Common.RestServiceProxyEngine.GetParameters(String clientID, String report, Dictionary`2 parameterValues)
at Telerik.ReportViewer.Common.ReportEngineRenderingController.GetParameters(ParameterCollection paramValues)
at Telerik.ReportViewer.Wpf.ReportViewerModel.ReloadParameters(IRenderingController controller)
at Telerik.ReportViewer.Wpf.ReportViewerModel.RefreshController(Boolean reloadParameters)
at Telerik.ReportViewer.Wpf.ReportViewerModel.RefreshReportCore(Boolean reloadParameters, LogHistoryRecord logHistory) 

[Ivan Hristov]

Hello Aleksey,

This is a known issue and it is logged in our product backlog for fixing in a subsequent release of our product. I absolutely agree that the error handling can be improved and it's really confusing to the user to reads incorrect exception messages.