Build model from result in Linqpad

I've done this recently a few times with Sqlite databases and also a while back with a SQL database.

I wanted to be able to use the dll in Visual studio and didn't want to depend on Linqpad, but did want to to be able to use it in Linqpad.

You don't have to do it this way, but the the process I used was something like this.

1. Select the database in LinqPad and run the script Util.OpenILSpy(typeof(TypedDataContext)); as a C# Expression.

2. In ILSpy, scroll up to the Assembly tab and right click on the dll which will have a name starting with TypedDataContext_ (see example screenshot)

3. Select Save Code from the context menu.

4. Open the selected folder and browse to the Subfolder LinqPad\User.

5. Copy the template csproj file into that folder and then open the project file. (Note ILSpy will have generated its own csproj file and you can use that and ignore the rest of the instructions if you don't mind a dependency on Linqpad)

6. Open TypedDataContext.cs

7. Remove the line using LINQPad.Drivers.EFCore;

8. Search for and replace ConnectionHelper.CurrentCxString ?? Util.CurrentCxString; with a empty string.

9. Search and replace TypedDataContext with my own Context

10. Search and replace namespace LINQPad.User with my own namespace.

11. Compile.

The csproj file template for Sqlite projects was

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

    <PropertyGroup>
        <TargetFramework>net6.0</TargetFramework>
        <ImplicitUsings>enable</ImplicitUsings>
        <Nullable>disable</Nullable>
    </PropertyGroup>

    <ItemGroup>
        <PackageReference Include="Microsoft.Data.Sqlite.Core" Version="6.0.8" />
        <PackageReference Include="Microsoft.EntityFrameworkCore" Version="6.0.8" />
        <PackageReference Include="Microsoft.EntityFrameworkCore.Proxies" Version="6.0.8" />
        <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="6.0.8" />
    </ItemGroup>
    <ItemGroup>
        <Reference Include="Microsoft.EntityFrameworkCore">
        </Reference>
        <Reference Include="Microsoft.EntityFrameworkCore.Proxies">
        </Reference>
        <Reference Include="Microsoft.EntityFrameworkCore.Sqlite">
        </Reference>
        <Reference Include="Microsoft.EntityFrameworkCore.Relational">
        </Reference>
    </ItemGroup>
</Project>

and I think the one for SQL was

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

  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>disable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="6.0.8" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Proxies" Version="6.0.8" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="6.0.8" />
  </ItemGroup>
    <ItemGroup>
        <Reference Include="Microsoft.EntityFrameworkCore">
        </Reference>
        <Reference Include="Microsoft.EntityFrameworkCore.Proxies">
        </Reference>
        <Reference Include="Microsoft.EntityFrameworkCore.Relational">
        </Reference>
    </ItemGroup>
</Project>
 

Obviously this depends on net6.0 and a specific version of EF, but you get the idea.

To a degree, you can automate this too using the package `ICSharpCode.Decompiler`.

In my LINQPad query I added a connection to a local SQLite database.

Batches is a class auto-generated by LINQPad using an EF Core connection.

string dll = typeof(Batches).Assembly.Location;
var decompiler = new CSharpDecompiler(dll, new DecompilerSettings { ThrowOnAssemblyResolveErrors = false});

var fullTypeNames = decompiler.TypeSystem.MainModule.TypeDefinitions
.Where(x => x.FullTypeName.Name == "Batches")
.Select(x => new {
    type = x.FullTypeName,
    code = decompiler.DecompileTypeAsString(x.FullTypeName)
})
.ToList()
;

fullTypeNames.Dump();

output looks like