ListViewItem in Vb.Net .Net 5

Question

I am migrating one Vb.Net Project into .Net 5.

Dim lvi As ListViewItem = ListView1.SelectedItems(0)

Error :

error BC30002: Type 'ListViewItem' is not defined

Can anybody please let me know How can I migrate ?

Best Regards
Mrutyunjaya

Answer 1

Hi,
please check count:

If ListView1.SelectedItems.Count > 0 Then
  Dim lvi As ListViewItem = ListView1.SelectedItems(0)
  Debug.Print(lvi.Text)
End If

Answer 2

This is what will work with a VB .NET project set to use .NET 5 without adding any references to the project.

Full source

• Front end project source code.
• Back end project support source code.

Language extension

Imports System.Reflection
Imports System.Runtime.CompilerServices

Public Module ListViewExtensions
    <Extension>
    Public Function GetSelectedItem(listView1 As ListView) As ListViewItem
        Return (If(listView1.SelectedItems.Count > 0, listView1.SelectedItems(0), Nothing))
    End Function
End Module

Example adding a new item

Private Async Sub OnTraverseEvent(information As DirectoryItem)

    Await Task.Delay(100)

    FoldersListView.InvokeIfRequired(Sub(listView)
                                         Dim item = New ListViewItem(information.ItemArray)
                                         item.Tag = information
                                         listView.Items.Add(item)
                                     End Sub)

    ProcessingLabel.InvokeIfRequired(Sub(label)
                                         label.Text = $"{FoldersListView.Items.Count}"
                                     End Sub)


End Sub

Get current selection, here from a context menu

Private Sub OpenFolderContextMenuStrip_Opening(sender As Object, e As ComponentModel.CancelEventArgs) _
    Handles OpenFolderContextMenuStrip.Opening

    If FoldersListView.Items.Count = 0 Then
        e.Cancel = True
    Else
        Dim selected = FoldersListView.GetSelectedItem()
    End If

End Sub

Project file (note references)

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

  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net5.0-windows</TargetFramework>
    <RootNamespace>RecurseFolders</RootNamespace>
    <StartupObject>Sub Main</StartupObject>
    <UseWindowsForms>true</UseWindowsForms>
    <MyType>WindowsForms</MyType>
    <OptionStrict>On</OptionStrict>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
    <WarningsAsErrors>41999,42016,42017,42018,42019,42020,42021,42022,42032,42036</WarningsAsErrors>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
    <WarningsAsErrors>41999,42016,42017,42018,42019,42020,42021,42022,42032,42036</WarningsAsErrors>
  </PropertyGroup>

  <ItemGroup>
    <Import Include="System.Data" />
    <Import Include="System.Drawing" />
    <Import Include="System.Windows.Forms" />
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\FileHelpers\FileHelpers.vbproj" />
    <ProjectReference Include="..\FolderBrowserDialog\FolderBrowserDialog.csproj" />
  </ItemGroup>

  <ItemGroup>
    <Compile Update="My Project\Application.Designer.vb">
      <DesignTime>True</DesignTime>
      <AutoGen>True</AutoGen>
      <DependentUpon>Application.myapp</DependentUpon>
    </Compile>
    <Compile Update="My Project\Resources.Designer.vb">
      <DesignTime>True</DesignTime>
      <AutoGen>True</AutoGen>
      <DependentUpon>Resources.resx</DependentUpon>
    </Compile>
  </ItemGroup>

  <ItemGroup>
    <EmbeddedResource Update="My Project\Resources.resx">
      <CustomToolNamespace>My.Resources</CustomToolNamespace>
      <Generator>VbMyResourcesResXFileCodeGenerator</Generator>
      <LastGenOutput>Resources.Designer.vb</LastGenOutput>
    </EmbeddedResource>
  </ItemGroup>

  <ItemGroup>
    <None Update="My Project\Application.myapp">
      <Generator>MyApplicationCodeGenerator</Generator>
      <LastGenOutput>Application.Designer.vb</LastGenOutput>
    </None>
  </ItemGroup>

</Project>