Why can a class not have a static or constant property and an instance property of the same name?

Question

I've never really questioned this before until now. I've got an input model with a number of fields, I wanted to present the string names of the properties through the input model so that my Grid can use them:

public class SomeGridRow
{
    public string Code { get;set; }
    public string Description { get;set; }

    public const string Code = "Code";
}

Obviously, this gives the error:

The type 'SomeGridRow' already contains a definition for 'Code'

Why can the CLR not cope with two properties of the same name which are, in my eyes, separate?

string code = gridRow.Code;          // Actual member from instantiated class
string codeField = SomeGridRow.Code; // Static/Const

I'm now just using a child class called Fields within my inputs now, so I can use SomeGridRow.Fields.Code . It's a bit messy, but it works.

Answer 1

Because you can also access static (or, non-instance in this case) properties in the same way (inside the same class), and it would be a bit confusing, for example:

public class SomeGridRow
{
  public string Code { get;set; }
  public const string Code = "Code";
  public void MyMethod() {
    var thing = Code; //what would this reference?
  }
}

Because both this:

public class SomeGridRow
{
  public string Code { get;set; }
  public void MyMethod() {
    var thing = Code; //what would this reference?
  }
}

And this:

public class SomeGridRow
{
  public const string Code = "Code";
  public void MyMethod() {
    var thing = Code; //what would this reference?
  }
}

are valid ways to access properties, static or not. It doesn't answer the "why can't I?" question, but more of the why it's not allowed...it would be far too ambiguous IMO.

Answer 2

It probably could, but the designers of C# wanted to avoid ambiguities that can come from such use (abuse?) of language features.

Such code would end up being confusing and ambiguous to users (did I want the instance or the static method call?, Which one is right?).

Answer 3

In addition to the points already made about ambiguity, i would say that the naming needs to be relooked in such a case.

If two variables / fields having the exact same name in the same context ie class but different values to me sounds more like a naming issue.

If they are exactly same, you dont need 2 fields.

If they are slightly different, you should have more accurate names.

Answer 4

In some other languages with a similar syntax, one can access a static member through an instance. So you could access both string.Empty and "abc".Empty .

C# doesn't allow this (though it does sort of from inside the class or a derived class, in that you can omit the class name for a static member and can omit this for an instance member), primarily to avoid confusion (I find it more handy than confusion tbh, but that's just me, I like switch fall-through too so what do I know).

Having introduced a stricter rule to allow for less ambiguity, it would be counterproductive to allow a new looser rule on the back of it that allowed for more. Think how many "why must I use this with property X but not property Y?" questions SO would have if it was allowed (we'd have to force this with property X to be clear we meant the instance member).