'T' does not contain a definition

Question

Is it possible to do the following (If so I can\'t seem to get it working.. forgoing constraints for the moment)...

If the type (because it\'s ommitted) is inferred,

Answer 1

No, it's not possible. Generic types must be known at compile time. Think about it for a minute, how could compiler know that it is guaranteed that the type T has SpreadsheetLineNumbers property? What if T is primitive type such as int or object ?

What prevents us from calling method with ref _, 999 parameters (T is int here) ?

It'd only work if we add an interface that contains this property :

public interface MyInterface 
{
    string SpreadsheetLineNumbers { get; set; }
}

And let your class inherit from this interface

public class MyClass : MyInterface
{
    public string SpreadsheetLineNumbers { get; set; }
}

Then we could use generic type constraints to let compiler know that the type T derives from this interface and therefore it has to contain and implement all its members:

private void GetGenericTableContent(ref StringBuilder outputTableContent, T item) 
    where T : IMyInterface // now compiler knows that T type has implemented all members of the interface
{
    outputTableContent.Append("" + item.SpreadsheetLineNumbers + "");
}