TypeConverters for System.Drawing

[qmfrederik]

TypeConverters are currently omitted from System.Drawing.Common, as described in dotnet/corefx#20593.

Since the idea is that Mono will use the CoreFX System.Drawing sources, and Mono maintains compatibility with Desktop .NET, we should add them back.

Here's what I can do:

• Add the TypeConverters (possibly from Mono) to CoreFX
• Add the TypeConverter attributes to the System.Drawing classes and hide them between a feature flag.

The same will probably apply other Desktop-only features, such as [Serializable] attributes.

[qmfrederik]

/cc @mellinoe @akoeplinger

[danmoseley]

We are limiting the types we apply Serializable to so if you have new such attributes we might want to put them on mono specific partial classes.

[danmoseley]

@weshaggard @morganbr I wonder if we need an analyzer to flag if more [serializable]'s appear.

[weshaggard]

As for the TypeConverters assuming we add them I would like to keep the in the TypeConverters library instead of System.Drawing.Common library if at all possible. We have been trying to invert this dependency to avoid everything needing to depend on TypeConverter.

[safern]

@qmfrederik interested on grabbing this one?

[qmfrederik]

@safern What's the timeline for this?

[safern]

It would be great to have this in the 2.1 timeline so that when we ship the stable Compat pack and 2.1 we have this compatibility with Desktop and Mono could use our implementation.

We're currently in prepping preview1 release which we don't have a date yet, but it would be nice to get this one any time soon.

[satano]

I would try to do this one. I just need to explain a what should be done. What converters to take and where to put them.

[safern]

@satano I found we're currently missing:

• FontConverter
• IconConverter
• ImageConverter
• ImageFormatConverter

We would need to port them from Mono:
https://github.com/mono/mono/blob/master/mcs/class/System.Drawing/System.Drawing/IconConverter.cs

Put them into System.ComponentModel.TypeConverter and then add the attributes to the corresponding types.

@qmfrederik is there any TypeConverter that I missed?

[satano]

OK. I'll do it.

[safern]

Assigned to you. Thanks!

[safern]

@satano any progress o this? Do you have any questions?

[satano]

I am doing this locally. In couple of days I will submit first version and will have questions there - it will be better to have context.