ListView.Clear-Methode

Entfernt alle Elemente und Spalten aus dem Steuerelement.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

Syntax

'Declaration
Public Sub Clear
'Usage
Dim instance As ListView

instance.Clear

public void Clear ()

public:
void Clear ()

public void Clear ()

public function Clear ()

Hinweise

Mithilfe dieser Methode können Sie alle Elemente und Spalten aus dem ListView-Steuerelement entfernen, ohne dass Sie die einzelnen Clear-Methoden aus der ListView.ColumnHeaderCollection-Klasse und der ListView.ListViewItemCollection-Klasse aufrufen müssen.

Beispiel

Im folgenden Codebeispiel wird die Verwendung des Clear-Members und des ListViewItem.Selected-Members veranschaulicht. Fügen Sie zum Ausführen dieses Beispiels den folgenden Code in ein Formular ein, das die ListViewListView1 und die Schaltfläche Button1 enthält, die sich im unteren Teil des Formulars befindet. Rufen Sie die InitializeListView-Methode aus dem Konstruktor des Formulars oder die Load-Methode auf.

Private Sub InitializeListView()

    ' Set up the inital values for the ListView and populate it.
    Me.ListView1 = New ListView
    Me.ListView1.Dock = DockStyle.Top
    Me.ListView1.Location = New System.Drawing.Point(0, 0)
    Me.ListView1.Size = New System.Drawing.Size(292, 130)
    Me.ListView1.View = View.Details
    Me.ListView1.FullRowSelect = True

    Dim breakfast() As String = New String() {"Continental Breakfast", "Pancakes and Sausage", _
   "Denver Omelet", "Eggs & Bacon", "Bagel & Cream Cheese"}

    Dim breakfastPrices() As String = New String() {"3.09", "4.09", "4.19", _
       "4.79", "2.09"}

    PopulateMenu("Breakfast", breakfast, breakfastPrices)
End Sub

Private Sub PopulateMenu(ByVal meal As String, _
    ByVal menuItems() As String, ByVal menuPrices() As String)
    Dim columnHeader1 As New ColumnHeader
    With columnHeader1
        .Text = meal & " Choices"
        .TextAlign = HorizontalAlignment.Left
        .Width = 146
    End With
    Dim columnHeader2 As New ColumnHeader
    With columnHeader2
        .Text = "Price"
        .TextAlign = HorizontalAlignment.Center
        .Width = 142
    End With
    Me.ListView1.Columns.Add(columnHeader1)
    Me.ListView1.Columns.Add(columnHeader2)

    Dim count As Integer

    For count = 0 To menuItems.Length - 1
        Dim listItem As New ListViewItem(menuItems(count))
        listItem.SubItems.Add(menuPrices(count))
        ListView1.Items.Add(listItem)
    Next

    ' Use the Selected property to select the first item on 
    ' the list.
    ListView1.Focus()
    ListView1.Items(0).Selected = True
End Sub


Private Sub Button1_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles Button1.Click

    ' Create new values for the ListView, clear the list, 
    ' and repopulate it.
    Dim lunch() As String = New String() {"Hamburger", _ 
        "Grilled Cheese", "Soup & Salad", "Club Sandwich", "Hotdog"}

    Dim lunchPrices() As String = New String() {"4.09", "5.09", _
        "5.19", "4.79", "2.09"}

    ListView1.Clear()

    PopulateMenu("Lunch", lunch, lunchPrices)
    Button1.Enabled = False
End Sub

private void InitializeListView()
{
    // Set up the inital values for the ListView and populate it.
    this.ListView1 = new ListView();
    this.ListView1.Dock = DockStyle.Top;
    this.ListView1.Location = new System.Drawing.Point(0, 0);
    this.ListView1.Size = new System.Drawing.Size(292, 130);
    this.ListView1.View = View.Details;
    this.ListView1.FullRowSelect = true;

    string[] breakfast = new string[]{"Continental Breakfast", 
        "Pancakes and Sausage", "Denver Omelet", "Eggs & Bacon", 
        "Bagel & Cream Cheese"};

    string[] breakfastPrices = new string[]{"3.09", "4.09", 
        "4.19", "4.79", "2.09"};

    PopulateMenu("Breakfast", breakfast, breakfastPrices);
}

private void PopulateMenu(string meal, 
    string[] menuItems, string[] menuPrices)
{
    ColumnHeader columnHeader1 = new ColumnHeader();
    columnHeader1.Text = meal + " Choices";
    columnHeader1.TextAlign = HorizontalAlignment.Left;
    columnHeader1.Width = 146;

    ColumnHeader columnHeader2 = new ColumnHeader();
    columnHeader2.Text = "Price";
    columnHeader2.TextAlign = HorizontalAlignment.Center;
    columnHeader2.Width = 142;

    this.ListView1.Columns.Add(columnHeader1);
    this.ListView1.Columns.Add(columnHeader2);

    for(int count=0; count < menuItems.Length; count++)
    {
        ListViewItem listItem = 
            new ListViewItem(menuItems[count]);
        listItem.SubItems.Add(menuPrices[count]);
        ListView1.Items.Add(listItem);
    }

    // Use the Selected property to select the first item on 
    // the list.
    ListView1.Focus();
    ListView1.Items[0].Selected = true;
}


private void Button1_Click(System.Object sender, System.EventArgs e)
{
    // Create new values for the ListView, clear the list, 
    // and repopulate it.
    string[] lunch = new string[]{"Hamburger", "Grilled Cheese",
        "Soup & Salad", "Club Sandwich", "Hotdog"};

    string[] lunchPrices = new string[]{"4.09", "5.09", "5.19", 
        "4.79", "2.09"};

    ListView1.Clear();

    PopulateMenu("Lunch", lunch, lunchPrices);
    Button1.Enabled = false;
}

private:
   void InitializeListView()
   {
      // Set up the inital values for the ListView and populate it.
      this->ListView1 = gcnew ListView;
      this->ListView1->Dock = DockStyle::Top;
      this->ListView1->Location = System::Drawing::Point( 0, 0 );
      this->ListView1->Size = System::Drawing::Size( 292, 130 );
      this->ListView1->View = View::Details;
      this->ListView1->FullRowSelect = true;
      array<String^>^breakfast = {"Continental Breakfast","Pancakes and Sausage","Denver Omelet","Eggs & Bacon","Bagel & Cream Cheese"};
      array<String^>^breakfastPrices = {"3.09","4.09","4.19","4.79","2.09"};
      PopulateMenu( "Breakfast", breakfast, breakfastPrices );
   }

   void PopulateMenu( String^ meal, array<String^>^menuItems, array<String^>^menuPrices )
   {
      ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
      columnHeader1->Text = String::Concat( meal, " Choices" );
      columnHeader1->TextAlign = HorizontalAlignment::Left;
      columnHeader1->Width = 146;
      ColumnHeader^ columnHeader2 = gcnew ColumnHeader;
      columnHeader2->Text = "Price";
      columnHeader2->TextAlign = HorizontalAlignment::Center;
      columnHeader2->Width = 142;
      this->ListView1->Columns->Add( columnHeader1 );
      this->ListView1->Columns->Add( columnHeader2 );
      for ( int count = 0; count < menuItems->Length; count++ )
      {
         ListViewItem^ listItem = gcnew ListViewItem( menuItems[ count ] );
         listItem->SubItems->Add( menuPrices[ count ] );
         ListView1->Items->Add( listItem );

      }
      
      // Use the Selected property to select the first item on 
      // the list.
      ListView1->Focus();
      ListView1->Items[ 0 ]->Selected = true;
   }

   void Button1_Click( System::Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      // Create new values for the ListView, clear the list, 
      // and repopulate it.
      array<String^>^lunch = {"Hamburger","Grilled Cheese","Soup & Salad","Club Sandwich","Hotdog"};
      array<String^>^lunchPrices = {"4.09","5.09","5.19","4.79","2.09"};
      ListView1->Clear();
      PopulateMenu( "Lunch", lunch, lunchPrices );
      Button1->Enabled = false;
   }

private void InitializeListView()
{
    // Set up the inital values for the ListView and populate it.
    this.listView1 = new ListView();
    this.listView1.set_Dock(DockStyle.Top);
    this.listView1.set_Location(new System.Drawing.Point(0, 0));
    this.listView1.set_Size(new System.Drawing.Size(292, 130));
    this.listView1.set_View(View.Details);
    this.listView1.set_FullRowSelect(true);

    String breakfast[] = new String[] { "Continental Breakfast",
        "Pancakes and Sausage", "Denver Omelet", "Eggs & Bacon",
        "Bagel & Cream Cheese" };

    String breakfastPrices[] = new String[] { "3.09", "4.09", "4.19",
        "4.79", "2.09" };

    PopulateMenu("Breakfast", breakfast, breakfastPrices);
} //InitializeListView

private void PopulateMenu(String meal,String menuItems[],String menuPrices[])
{
    ColumnHeader columnHeader1 = new ColumnHeader();
    columnHeader1.set_Text(meal + " Choices");
    columnHeader1.set_TextAlign(HorizontalAlignment.Left);
    columnHeader1.set_Width(146);

    ColumnHeader columnHeader2 = new ColumnHeader();
    columnHeader2.set_Text("Price");
    columnHeader2.set_TextAlign(HorizontalAlignment.Center);
    columnHeader2.set_Width(142);

    this.listView1.get_Columns().Add(columnHeader1);
    this.listView1.get_Columns().Add(columnHeader2);

    for (int count = 0; count < menuItems.length; count++) {
        ListViewItem listItem =
            new ListViewItem((String)menuItems.get_Item(count));
        listItem.get_SubItems().Add((String)menuPrices.get_Item(count));
        listView1.get_Items().Add(listItem);
    }
    // Use the Selected property to select the first item on 
    // the list.
    listView1.Focus();
    listView1.get_Items().get_Item(0).set_Selected(true);
} //PopulateMenu

private void button1_Click(System.Object sender, System.EventArgs e)
{
    // Create new values for the ListView, clear the list, 
    // and repopulate it.
    String lunch[] = new String[] { "Hamburger", "Grilled Cheese",
        "Soup & Salad", "Club Sandwich", "Hotdog" };

    String lunchPrices[] = new String[] { "4.09", "5.09", "5.19",
        "4.79", "2.09" };

    listView1.Clear();

    PopulateMenu("Lunch", lunch, lunchPrices);
    button1.set_Enabled(false);
} //button1_Click

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

ListView-Klasse
ListView-Member
System.Windows.Forms-Namespace
ListView.ColumnHeaderCollection.Clear
ListView.ListViewItemCollection.Clear