"Object reference not set to an instance of an object" Exception When Using A DetailsView Control In ASP.NET
I ran into an exception recently when developing a website in ASP.NET which made use of a DetailsView control bound to an ADO.NET Entity Data Model as its data source (EntityDataSource). The complete exception message was: [NullReferenceException: Object reference not set to an instance of an object.] System.Web.UI.WebControls.EntityDataSourceView.ConvertWCProperty(IDictionary values, Dictionary`2 convertedValues, List`1 visitedProperties, PropertyDescriptor pd, ParameterCollection referenceParameters, Dictionary`2& exceptions) +35 System.Web.UI.WebControls.EntityDataSourceView.ConvertProperties(IDictionary values, PropertyDescriptorCollection propertyDescriptors, ParameterCollection referenceParameters) +216 System.Web.UI.WebControls.EntityDataSourceView.CreateEntityForInsert(EntityDataSourceWrapper entityWrapper, IDictionary values, ParameterCollection insertParameters) +49 System.Web.UI.WebControls.EntityDataSourceView.ExecuteInsert(IDictionary values) +239 System