How to allow user to set expressions detrmining property value in PropertyGrid

Question

I noticed that programs like Report Builder allow user to set property value or an expression determining property value. I want to the add same functionality to my application. So is there any simple way to do so or do i have to redefine all type converters so that they allow to set expression in addition to their original functionality.

Answer 1

Maybe it's easier to override the Property-Grid-Control to add this kind of functionality to every property.

I am just curious, how do you evaluate those expressions (CodeDOM) ?

Answer 2

If you want to create your own "drop-down properties", you need to implement a custom UITypeEditor.

There are several samples for that:

• http://www.codeproject.com/KB/cpp/dropdownproperties.aspx
• http://msdn.microsoft.com/en-us/library/ms171840.aspx
• http://www.eggheadcafe.com/tutorials/aspnet/270e9432-d236-47e7-b1af-5cd3abe27a75/net-propertygrid-control.aspx
• http://www.devx.com/dotnet/Article/20920/1954?pf=true

Answer 3

This is exposed via TypeConverter.

To allow string input, the object must be convertible from type string.

To allow a drop down, expose the values via GetStandardValues.

You will need to override the xxxSupported methods too.