"D.Z. Simpson" <d_z_simpson@yahoo.com> wrote in message
news:uEl$HA4XFHA.4000@TK2MSFTNGP10.phx.gbl...
> Using the following ExpandableObjectConverter-derived class leads to a
> most strange issue. The ConvertTo method receives an 'Object value'
> argument that is supposed to be of my own Style class. That Style class is
> used as the type of several properties in my custom control.
>
> Now that works fine while there is only my control on a form. But after
> another control of any kind is added, some strange things begin to
> happen - from time to time the 'Object value' arguments passed to the
> convertor cannot be casted any longer to the Style class - neither using
> '(Style)value' nor 'value as Style' constructs. The funny thing is that
> the watch in VS debugger really shows the value object as a Style instance
> with all its members having appropriate values.
>
> Can anyone please explain why ConvertTo is called with a value that cannot
> be casted to my Style class, and still the debugger shows that value as a
> perfect Style instance in the watch window? Thanks in advance, any logical
> explanation will hopefully save me from utter madness.
>
> internal class StyleConverter : ExpandableObjectConverter
> {
> public override bool CanConvertTo(
> ITypeDescriptorContext context, Type destinationType)
> {
> if (destinationType == typeof(InstanceDescriptor))
> return true;
>
> return base.CanConvertTo(context, destinationType);
> }
>
> public override object ConvertTo(
> ITypeDescriptorContext context, System.Globalization.CultureInfo
> culture,
> object value, Type destinationType)
> {
> Style style = value as Style;
> if (destinationType == typeof(InstanceDescriptor) && style != null)
> {
> ConstructorInfo info = typeof(Style).GetConstructor(
> new Type[] { typeof(string) });
>
> if (info != null)
> return new InstanceDescriptor(info, new object[] { style.Store() });
> }
>
> return base.ConvertTo(context, culture, value, destinationType);
> }
> }
>

> Is this a nested class? Some strange things like this happen when you nest
> classes, structs or enums. If so, try moving it outside of any class, but
> within a namespace.
>
> --
> Mick Doherty
> http://dotnetrix.co.uk/nothing.html

"D.Z. Simpson" <d_z_simpson@yahoo.com> wrote in message
news:uEl$HA4XFHA.4000@TK2MSFTNGP10.phx.gbl...
> Using the following ExpandableObjectConverter-derived class leads to a
> most strange issue. The ConvertTo method receives an 'Object value'
> argument that is supposed to be of my own Style class. That Style class is
> used as the type of several properties in my custom control.
>
> Now that works fine while there is only my control on a form. But after
> another control of any kind is added, some strange things begin to
> happen - from time to time the 'Object value' arguments passed to the
> convertor cannot be casted any longer to the Style class - neither using
> '(Style)value' nor 'value as Style' constructs. The funny thing is that
> the watch in VS debugger really shows the value object as a Style instance
> with all its members having appropriate values.
>
> Can anyone please explain why ConvertTo is called with a value that cannot
> be casted to my Style class, and still the debugger shows that value as a
> perfect Style instance in the watch window? Thanks in advance, any logical
> explanation will hopefully save me from utter madness.
>
> internal class StyleConverter : ExpandableObjectConverter
> {
> public override bool CanConvertTo(
> ITypeDescriptorContext context, Type destinationType)
> {
> if (destinationType == typeof(InstanceDescriptor))
> return true;
>
> return base.CanConvertTo(context, destinationType);
> }
>
> public override object ConvertTo(
> ITypeDescriptorContext context, System.Globalization.CultureInfo
> culture,
> object value, Type destinationType)
> {
> Style style = value as Style;
> if (destinationType == typeof(InstanceDescriptor) && style != null)
> {
> ConstructorInfo info = typeof(Style).GetConstructor(
> new Type[] { typeof(string) });
>
> if (info != null)
> return new InstanceDescriptor(info, new object[] { style.Store() });
> }
>
> return base.ConvertTo(context, culture, value, destinationType);
> }
> }
>

"Frank Hileman" <frankhil@no.spamming.prodigesoftware.com> wrote in message
news:u%23CQKyFYFHA.2740@TK2MSFTNGP14.phx.gbl...
> In this situation you probably have two copies of your dll loaded. Both
> have a Style class, but they are not considered the same class by the
> designer (one loaded via LoadFrom, one via Load). Are you using reflection
> at design-time on this dll? If so, eliminate that, as it will cause
> problems.
>
> If not, try strong naming your dll and installing in the GAC. This will
> help prevent it from being loaded twice. Also search for old copies of
> your dll being referenced, possibly from a bin folder.
>
> Regards,
> Frank Hileman
>
> check out VG.net: http://www.vgdotnet.com
> Animated vector graphics system
> Integrated Visual Studio .NET graphics editor
>
> "D.Z. Simpson" <d_z_simpson@yahoo.com> wrote in message
> news:uEl$HA4XFHA.4000@TK2MSFTNGP10.phx.gbl...
>> Using the following ExpandableObjectConverter-derived class leads to a
>> most strange issue. The ConvertTo method receives an 'Object value'
>> argument that is supposed to be of my own Style class. That Style class
>> is used as the type of several properties in my custom control.
>>
>> Now that works fine while there is only my control on a form. But after
>> another control of any kind is added, some strange things begin to
>> happen - from time to time the 'Object value' arguments passed to the
>> convertor cannot be casted any longer to the Style class - neither using
>> '(Style)value' nor 'value as Style' constructs. The funny thing is that
>> the watch in VS debugger really shows the value object as a Style
>> instance with all its members having appropriate values.
>>
>> Can anyone please explain why ConvertTo is called with a value that
>> cannot be casted to my Style class, and still the debugger shows that
>> value as a perfect Style instance in the watch window? Thanks in advance,
>> any logical explanation will hopefully save me from utter madness.
>>
>> internal class StyleConverter : ExpandableObjectConverter
>> {
>> public override bool CanConvertTo(
>> ITypeDescriptorContext context, Type destinationType)
>> {
>> if (destinationType == typeof(InstanceDescriptor))
>> return true;
>>
>> return base.CanConvertTo(context, destinationType);
>> }
>>
>> public override object ConvertTo(
>> ITypeDescriptorContext context, System.Globalization.CultureInfo
>> culture,
>> object value, Type destinationType)
>> {
>> Style style = value as Style;
>> if (destinationType == typeof(InstanceDescriptor) && style != null)
>> {
>> ConstructorInfo info = typeof(Style).GetConstructor(
>> new Type[] { typeof(string) });
>>
>> if (info != null)
>> return new InstanceDescriptor(info, new object[] { style.Store() });
>> }
>>
>> return base.ConvertTo(context, culture, value, destinationType);
>> }
>> }
>>
>
>