Context selection cannot be null

Please check once the full stack trace for further reference. IIS doesn't really "render" anything. It clearly happens while ASP. It could be that you assign a text property that is later used as an integer that from some reason it is sometimes null for example it is taken from a Session variable and the Session expired. No session on that page.

No convert method on that page which will try to convert null value to int It should allow to better understand which part is causing this issue. This is an umbraco site so no aspx page is there.

Only master page with including macros known as user control is there. Value cannot be null. Do you mean you really tried my suggestion? Nobody wrote this code. I'm trying to explain that ASCX files are turned into source code file which is then compiled. The error happens inside this generated code The content you requested has been removed. Ask a question. Quick access. Search related threads. Star New issue. Jump to bottom. This method or property cannot be called on Null values.

Labels closed-duplicate customer-reported. Copy link. This issue has already been reported a few other times in: I'm using Entity Framework Core 2. Generic; using System. DataAnnotations; using System. Schema; namespace MyApplication. ForSqlServerIsClustered false ; entity.

HasName "CustomersCompanyName" ; entity. IsUnicode false. ValueGeneratedNever ; entity. HasDefaultValueSql " 'Standard' " ; entity. IsUnicode false ; entity. HasDefaultValueSql " 'Company' " ; entity. MoveNext at System. GetEnumerator at Microsoft. Execute[TResult] Expression query at Microsoft. Execute[TResult] Expression expression at System.

Execute Object target, Object[] parameters at Microsoft. UseLoggerFactory Logger. You can also declare nullable value types. Nullable reference types are available beginning with C 8. Nullable reference types, the null static analysis warnings, and the null-forgiving operator are optional language features. All are turned off by default. A nullable context is controlled at the project level using build settings, or in code using pragmas.

The distinctions between a non-nullable reference type T and a nullable reference type T? A variable of type T and a variable of type T? NET type. The following example declares a non-nullable string and a nullable string, and then uses the null-forgiving operator to assign a value to a non-nullable string:. The variables notNull and nullable are both represented by the String type. Because the non-nullable and nullable types are both stored as the same type, there are several locations where using a nullable reference type isn't allowed.

In general, a nullable reference type can't be used as a base class or implemented interface. A nullable reference type can't be used in any object creation or type testing expression. A nullable reference type can't be the type of a member access expression. The following examples show these constructs:.

The examples in the previous section illustrate the nature of nullable reference types. Nullable reference types aren't new class types, but rather annotations on existing reference types. The compiler uses those annotations to help you find potential null reference errors in your code.

There's no runtime difference between a non-nullable reference type and a nullable reference type. The compiler doesn't add any runtime checking for non-nullable reference types. The benefits are in the compile-time analysis. The compiler generates warnings that help you find and fix potential null errors in your code. You declare your intent, and the compiler warns you when your code violates that intent.