Why can't Point and Rectangle be used as optional parameters?

Question

I'm trying to pass an optional argument to a geometry function, called offset, which may or may not be specified, but C# doesn't allow me to do any of the following. Is there a way to accomplish this?

Null as default

Error: A value of type '' cannot be used as a default parameter because there are no standard conversions to type 'System.Drawing.Point'
```
public void LayoutRelative(.... Point offset = null) {} 
```
Empty as default

Error: Default parameter value for 'offset' must be a compile-time constant
```
public void LayoutRelative(.... Point offset = Point.Empty) {} 
```

Adam · Accepted Answer · 2012-09-02 11:53:44Z

If your default value doesn't require any special initialization, you don't need to use a nullable type or create different overloads. You can use the default keyword:

public void LayoutRelative(.... Point offset = default(Point)) {}

If you want to use a nullable type instead:

public void LayoutRelative(.... Point? offset = null) { if (offset.HasValue) { DoSomethingWith(offset.Value); } }

Collectives™ on Stack Overflow

Why can't Point and Rectangle be used as optional parameters?

1 Answer 1

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Linked

Related