COMPILE ERROR when using custom controls w/ custom properties w/ custom TypeConverters

COMPILE ERROR when using custom controls w/ custom properties w/ custom TypeConverters

Post by Steve Rose » Wed, 16 Jul 2003 07:21:56

I have a custom control that has a custom property using the following

[ TypeConverter( typeof( MyPropertyConverter ) ) ]
public enum MyProperty { Value1, Value2, Value3 };

The TypeConverter does nothing more than convert the Value1 value to a
"Value 1" string for display in a property grid and vice versa. The
problem is that when I add my custom control to a form, the Component
Designer places the following line in my C# code:

this.MyCtrl.MyProp = MyProperty.Value 1;

Note the space between the "Value" and the "1" at the end. This results
in a compile error since there should be no space. I assume
MyPropertyConverter is messin' with me because I'm missing a conversion
required by the Component Designer to generate the correct
initialization value in the above statement.

AND FINALLY THE QUESTION: Does anyone know what that conversion type
should be? Or am I completely off-base? Thanks.

For reference, below is the MyPropertyConverter in all its glory:

class MyPropertyConverter : System.ComponentModel.TypeConverter

public override bool
GetStandardValuesSupported( ITypeDescriptorContext context )
{ return( true ); }

public override bool
GetStandardValuesExclusive( ITypeDescriptorContext context )
{ return( false ); }

public override StandardValuesCollection
GetStandardValues( ITypeDescriptorContext context )
MyProperty[] sv =
return( new StandardValuesCollection( sv ) );

public override bool
CanConvertFrom( ITypeDescriptorContext context,
Type sourceType )
if( sourceType == typeof( string ) ) return true;
return( base.CanConvertFrom( context, sourceType ) );

public override object
ConvertFrom( ITypeDescriptorContext context,
CultureInfo culture,
object value )
if( value is string )
switch( (string)value )
case "Value 1": return( MyProperty.Value1 );
case "Value 2": return( MyProperty.Value2 );
case "Value 3": return( MyProperty.Value3 );
return base.ConvertFrom( context, culture, value );

public override object
ConvertTo( ITypeDescriptorContext context,
CultureInfo culture,
object value,
Type destinationType )
if( destinationType == typeof( string ) )
if( value is MyProperty )
switch( (MyProperty)value )
case MyProperty.Value1: return( "Value 1" );
case MyProperty.Value2: return( "Value 2" );
case MyProperty.Value3: return( "Value 3" );
else if( value is string )
return( (string)value );
return base.ConvertTo( context, culture, value, destinationType );

} /**** class MyPropertyConverter ****/

Steve Rosenberry
Sr. Partner

Electronic Solutions Company -- For the Home of Integration

(610) 670-1710

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