[A]System.Drawing.Bitmap cannot be cast to [B]System.Drawing.Bitmap

mcnamaragio

I'm trying to port my custom visualizer from LINQPad 5 to LINQPad 6 and I get the following exception when I try to access one of the images in the Resources file that I have:

[A]System.Drawing.Bitmap cannot be cast to [B]System.Drawing.Bitmap. Type A originates from 'System.Drawing.Common, Version=5.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' in the context 'Default' at location 'C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App\5.0.0\System.Drawing.Common.dll'. Type B originates from 'System.Drawing.Common, Version=4.0.0.1, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' in the context 'Default' at location 'C:\Users\Giorgi\AppData\Local\Temp\LINQPad6\_iybtcson\shadow-13\System.Drawing.Common.dll'.

at System.Runtime.CompilerServices.CastHelpers.ChkCast_Helper(Void* toTypeHnd, Object obj) at QueryPlanVisualizer.LinqPad6.SqlServerResources.get_qp_icons() in D:\src\queryplanvisualizer\src\QueryPlanVisualizer.LinqPad6\SqlServerResources.Designer.cs:line 108 at QueryPlanVisualizer.LinqPad6.QueryPlanVisualizer.DumpPlanInternal[T](IQueryable`1 queryable, Boolean dumpData, Boolean addNewPanel) in D:\src\queryplanvisualizer\src\QueryPlanVisualizer.LinqPad6\QueryPlanVisualizer.cs:line 80 at QueryPlanVisualizer.LinqPad6.QueryPlanVisualizer.DumpPlan[T](IQueryable`1 queryable, Boolean dumpData) in D:\src\queryplanvisualizer\src\QueryPlanVisualizer.LinqPad6\QueryPlanVisualizer.cs:line 17

Any suggestions?

mcnamaragio

I "solved" the issue by embedding the image as "Embedded Resource" but now I get this exception when trying to set an image for button:

Method not found: 'Void System.Windows.Forms.ButtonBase.set_Image(System.Drawing.Image)'.

JoeAlbahari

It sounds like your visualizer project is targeting .NET Framework instead of .NET 5 or .NET Core 3. Because LINQPad 6 targets .NET 5 / .NET Core 3, your visualizer must do the same.

If you want to have a single project that supports both LINQPad 5 (.NET Framework) and LINQPad 6 (.NET 5 / .NET Core 3), you can multi-target. Here's an example of a .csproj file that multi-targets .NET Framework 4.6 and .NET Core 3.1. It will generate two output folders (bin\net46 and bin\netcoreapp3.1):

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">

    <PropertyGroup>
        <TargetFrameworks>netcoreapp3.1;net46</TargetFrameworks>
        <UseWpf>true</UseWpf>
    </PropertyGroup>

    <PropertyGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
        <DefineConstants>NETCORE</DefineConstants>
    </PropertyGroup>

    <ItemGroup Condition="'$(TargetFramework)' == 'net46'">
        <Reference Include="System.Xaml">
            <RequiredTargetFramework>4.0</RequiredTargetFramework>
        </Reference>
        <Reference Include="WindowsBase" />
        <Reference Include="PresentationCore" />
        <Reference Include="PresentationFramework" />
    </ItemGroup>

</Project>

Notice the conditional item groups. Any references to framework libraries such as System.Drawing.dll should exist only in the net46 item group, and not in the netcoreapp group.

mcnamaragio

My visualizer targets .net core but the error happens only when using a typed context from my own assembly that has a dependency on Microsoft.EntityFrameworkCore.SqlServer

mcnamaragio

This happens in LINQPad without referencing the visualizer but using a typed context that doesn't reference anything apart from Microsoft.EntityFrameworkCore.SqlServer