Object property with different return types

[Simbad]

I have a control 'MyControl' with a property of
type 'MyObject'. MyObject has a property 'MyField' that
is a enum type. I want the type of enum to vary
depending on a another property of MyObject
called 'MyFieldType'. E.g. if MyFieldType = TypeA,
MyField returns EnumA. See code below:

public enum FieldTypes
{
TypeA,
TypeB
}

public enum EnumA
{
Big,
Medium,
Small
}

public enum EnumB
{
Short,
Tall,
Squat,
Huge
}

[DefaultProperty("MyFieldType")]
public class MyObject
{
private FieldTypes m_MyFieldType;
private object m_MyField = 0;

public FieldTypes MyFieldType
{
get {return m_MyFieldType;}
set {m_MyFieldType = value;}
}

public object MyField
{
get
{
if (MyFieldType == FieldTypes.TypeA)
{
return (EnumA)m_MyField;
}
else
{
return (EnumB)m_MyField;
}
}
set
{
m_MyField = value;
}
}
}


My problem is that the MyField property is not editable
via a dropdown list in the designer. It appears as a
greyed-out (read only) string representation of the
respective enum (EnumA or EnumB). I've tried writing a
TypeConverter (inheriting from EnumConverter) but just
ended up going round in circles.

Does anyone have an example of what I'm trying to do or
point me in the right direction?

Thanks

[Teemu Keiski]

Hi,

I suspect that the property should be of only one type for it to work
correctly. You can't parameterize its type (the type needs to be fixed at
design-time).

--
Teemu Keiski
MCP, Microsoft MVP (ASP.NET), AspInsiders member
ASP.NET Forum Moderator, AspAlliance Columnist


"Simbad" <anonymous@discussions.microsoft.com> wrote in message
news:094a01c3d918$73f0a8a0$a101280a@phx.gbl...

>I have a control 'MyControl' with a property of
> type 'MyObject'. MyObject has a property 'MyField' that
> is a enum type. I want the type of enum to vary
> depending on a another property of MyObject
> called 'MyFieldType'. E.g. if MyFieldType = TypeA,
> MyField returns EnumA. See code below:
>
> public enum FieldTypes
> {
> TypeA,
> TypeB
> }
>
> public enum EnumA
> {
> Big,
> Medium,
> Small
> }
>
> public enum EnumB
> {
> Short,
> Tall,
> Squat,
> Huge
> }
>
> [DefaultProperty("MyFieldType")]
> public class MyObject
> {
> private FieldTypes m_MyFieldType;
> private object m_MyField = 0;
>
> public FieldTypes MyFieldType
> {
> get {return m_MyFieldType;}
> set {m_MyFieldType = value;}
> }
>
> public object MyField
> {
> get
> {
> if (MyFieldType == FieldTypes.TypeA)
> {
> return (EnumA)m_MyField;
> }
> else
> {
> return (EnumB)m_MyField;
> }
> }
> set
> {
> m_MyField = value;
> }
> }
> }
>
>
> My problem is that the MyField property is not editable
> via a dropdown list in the designer. It appears as a
> greyed-out (read only) string representation of the
> respective enum (EnumA or EnumB). I've tried writing a
> TypeConverter (inheriting from EnumConverter) but just
> ended up going round in circles.
>
> Does anyone have an example of what I'm trying to do or
> point me in the right direction?
>
> Thanks