ListViewGroupCollection Klasse

Definition

public ref class ListViewGroupCollection : System::Collections::IList

[System.ComponentModel.ListBindable(false)]
public class ListViewGroupCollection : System.Collections.IList

[<System.ComponentModel.ListBindable(false)>]
type ListViewGroupCollection = class
    interface IList
    interface ICollection
    interface IEnumerable

Public Class ListViewGroupCollection
Implements IList

Vererbung

Object

ListViewGroupCollection

Attribute

ListBindableAttribute

Implementiert

ICollection IEnumerable IList

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie Sie das ListView Gruppierungsfeature verwenden, um Elemente nach Unterelementwert in der Detailansicht zu organisieren. Diese Form der Gruppierung ähnelt der Gruppierung, die in Windows Explorer verwendet wird. Im Beispiel werden die Gruppen dynamisch erstellt. Für jede Unterelementspalte wird für jeden eindeutigen Unterelementwert eine Gruppe erstellt. Für die Spalte des übergeordneten Elements wird für jeden eindeutigen Anfangsbuchstaben eine Gruppe erstellt. Wenn Sie auf die Kopfzeile einer Spalte klicken, werden die Elemente in die Gruppen sortiert, die für diese Spalte erstellt wurden. Wenn Sie auf die gleiche Spaltenüberschrift klicken, wird die Reihenfolge der Gruppen erneut umgekehrt.

#using <mscorlib.dll>
#using <System.Drawing.dll>
#using <System.dll>
#using <System.Windows.Forms.dll>
using namespace System;
using namespace System::Collections; 
using namespace System::Windows::Forms;

public ref class ListViewGroupsExample : public Form
{
private:
   ListView^ myListView;
   bool isRunningXPOrLater;

   // Declare a Hashtable array in which to store the groups.
   array<Hashtable^>^ groupTables;

   // Declare a variable to store the current grouping column.
   int groupColumn;

public:
   ListViewGroupsExample()
   {
      groupColumn = 0;
      // Initialize myListView.
      myListView = gcnew ListView();
      myListView->Dock = DockStyle::Fill;
      myListView->View = View::Details;
      myListView->Sorting = SortOrder::Ascending;

      // Create and initialize column headers for myListView.
      ColumnHeader^ columnHeader0 = gcnew ColumnHeader();
      columnHeader0->Text = "Title";
      columnHeader0->Width = -1;
      ColumnHeader^ columnHeader1 = gcnew ColumnHeader();
      columnHeader1->Text = "Author";
      columnHeader1->Width = -1;
      ColumnHeader^ columnHeader2 = gcnew ColumnHeader();
      columnHeader2->Text = "Year";
      columnHeader2->Width = -1;

      // Add the column headers to myListView.

      array<ColumnHeader^>^ temp0 = {columnHeader0, columnHeader1, columnHeader2};
      myListView->Columns->AddRange(temp0);

      // Add a handler for the ColumnClick event.
      myListView->ColumnClick += 
         gcnew ColumnClickEventHandler(this, &ListViewGroupsExample::myListView_ColumnClick);

      // Create items and add them to myListView.

      array<String^>^ temp1 = {"Programming Windows", "Petzold, Charles", "1998"};
      ListViewItem^ item0 = gcnew ListViewItem( temp1 );

      array<String^>^ temp2 = {"Code: The Hidden Language of Computer Hardware and Software",
         "Petzold, Charles", "2000"};
      ListViewItem^ item1 = gcnew ListViewItem( temp2 );

      array<String^>^ temp3 = {"Programming Windows with C#", "Petzold, Charles", "2001"};
      ListViewItem^ item2 = gcnew ListViewItem( temp3 );

      array<String^>^ temp4 = {"Coding Techniques for Microsoft Visual Basic .NET",
         "Connell, John", "2001"};
      ListViewItem^ item3 = gcnew ListViewItem( temp4 );

      array<String^>^ temp5 = {"C# for Java Developers", "Jones, Allen & Freeman, Adam",
         "2002"};
      ListViewItem^ item4 = gcnew ListViewItem( temp5 );

      array<String^>^ temp6 = {"Microsoft .NET XML Web Services Step by Step",
         "Jones, Allen & Freeman, Adam", "2002"};
      ListViewItem^ item5 = gcnew ListViewItem( temp6 );

      array<ListViewItem^>^ temp7 = {item0, item1, item2, item3, item4, item5};
      myListView->Items->AddRange( temp7 );

      // Determine whether Windows XP or a later 
      // operating system is present.
      isRunningXPOrLater = false;

      if (System::Environment::OSVersion->Version->Major > 5 ||
         ( System::Environment::OSVersion->Version->Major == 5 &&
         System::Environment::OSVersion->Version->Minor >= 1) )
      {
         isRunningXPOrLater = true;
      }

      if (isRunningXPOrLater)
      {
         // Create the groupsTable array and populate it with one 
         // hash table for each column.
         groupTables = gcnew array<Hashtable^>(myListView->Columns->Count);
         for (int column = 0; column < myListView->Columns->Count; column++)
         {
            // Create a hash table containing all the groups 
            // needed for a single column.
            groupTables[column] = CreateGroupsTable(column);
         }

         // Start with the groups created for the Title column.
         SetGroups(0);
      }

      // Initialize the form.
      this->Controls->Add(myListView);
      this->Size = System::Drawing::Size(550, 330);
      this->Text = "ListView Groups Example";
   }

   // Groups the items using the groups created for the clicked 
   // column.
private:
   void myListView_ColumnClick(
      Object^ /*sender*/, ColumnClickEventArgs^ e)
   {
      // Set the sort order to ascending when changing
      // column groups; otherwise, reverse the sort order.
      if ( myListView->Sorting == SortOrder::Descending || 
         ( isRunningXPOrLater && (e->Column != groupColumn) ) )
      {
         myListView->Sorting = SortOrder::Ascending;
      }
      else 
      {
         myListView->Sorting = SortOrder::Descending;
      }
      groupColumn = e->Column;

      // Set the groups to those created for the clicked column.
      if (isRunningXPOrLater)
      {
         SetGroups(e->Column);
      }
   }

   // Sets myListView to the groups created for the specified column.
private:
   void SetGroups(int column)
   {
      // Remove the current groups.
      myListView->Groups->Clear();

      // Retrieve the hash table corresponding to the column.
      Hashtable^ groups = dynamic_cast<Hashtable^>(groupTables[column]);

      // Copy the groups for the column to an array.
      array<ListViewGroup^>^ groupsArray = gcnew array<ListViewGroup^>(groups->Count);
      groups->Values->CopyTo(groupsArray, 0);

      // Sort the groups and add them to myListView.
      Array::Sort(groupsArray, gcnew ListViewGroupSorter(myListView->Sorting));
      myListView->Groups->AddRange(groupsArray);

      // Iterate through the items in myListView, assigning each 
      // one to the appropriate group.
      IEnumerator^ myEnum = myListView->Items->GetEnumerator();
      while (myEnum->MoveNext())
      {
         ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
         // Retrieve the subitem text corresponding to the column.
         String^ subItemText = item->SubItems[column]->Text;

         // For the Title column, use only the first letter.
         if (column == 0) 
         {
            subItemText = subItemText->Substring(0, 1);
         }

         // Assign the item to the matching group.
         item->Group = dynamic_cast<ListViewGroup^>(groups[subItemText]);
      }
   }

   // Creates a Hashtable object with one entry for each unique
   // subitem value (or initial letter for the parent item)
   // in the specified column.
private:
   Hashtable^ CreateGroupsTable(int column)
   {
      // Create a Hashtable object.
      Hashtable^ groups = gcnew Hashtable();

      // Iterate through the items in myListView.
      IEnumerator^ myEnum1 = myListView->Items->GetEnumerator();
      while (myEnum1->MoveNext())
      {
         ListViewItem^ item = safe_cast<ListViewItem^>(myEnum1->Current);
         // Retrieve the text value for the column.
         String^ subItemText = item->SubItems[column]->Text;

         // Use the initial letter instead if it is the first column.
         if (column == 0) 
         {
            subItemText = subItemText->Substring(0, 1);
         }

         // If the groups table does not already contain a group
         // for the subItemText value, add a new group using the 
         // subItemText value for the group header and Hashtable key.
         if (!groups->Contains(subItemText))
         {
            groups->Add( subItemText, gcnew ListViewGroup(subItemText, 
               HorizontalAlignment::Left) );
         }
      }

      // Return the Hashtable object.
      return groups;
   }

   // Sorts ListViewGroup objects by header value.
   ref class ListViewGroupSorter : public IComparer
   {
   private:
      SortOrder order;

      // Stores the sort order.
   public:
      ListViewGroupSorter(SortOrder theOrder) 
      { 
         order = theOrder;
      }

      // Compares the groups by header value, using the saved sort
      // order to return the correct value.
      virtual int Compare(Object^ x, Object^ y)
      {
         int result = String::Compare(
            (dynamic_cast<ListViewGroup^>(x))->Header,
            (dynamic_cast<ListViewGroup^>(y))->Header
            );
         if (order == SortOrder::Ascending)
         {
            return result;
         }
         else 
         {
            return -result;
         }
      }
   };
};

[STAThread]
int main() 
{
   Application::EnableVisualStyles();
   Application::Run(gcnew ListViewGroupsExample());
}

using System;
using System.Collections; 
using System.Windows.Forms;

public class ListViewGroupsExample : Form
{
    private ListView myListView;

    // Determine whether Windows XP or a later
    // operating system is present.
    private bool isRunningXPOrLater = 
        OSFeature.Feature.IsPresent(OSFeature.Themes);

    // Declare a Hashtable array in which to store the groups.
    private Hashtable[] groupTables;

    // Declare a variable to store the current grouping column.
    int groupColumn = 0;

    public ListViewGroupsExample()
    {
        // Initialize myListView.
        myListView = new ListView();
        myListView.Dock = DockStyle.Fill;
        myListView.View = View.Details;
        myListView.Sorting = SortOrder.Ascending;

        // Create and initialize column headers for myListView.
        ColumnHeader columnHeader0 = new ColumnHeader();
        columnHeader0.Text = "Title";
        columnHeader0.Width = -1;
        ColumnHeader columnHeader1 = new ColumnHeader();
        columnHeader1.Text = "Author";
        columnHeader1.Width = -1;
        ColumnHeader columnHeader2 = new ColumnHeader();
        columnHeader2.Text = "Year";
        columnHeader2.Width = -1;

        // Add the column headers to myListView.
        myListView.Columns.AddRange(new ColumnHeader[] 
            {columnHeader0, columnHeader1, columnHeader2});

        // Add a handler for the ColumnClick event.
        myListView.ColumnClick += 
            new ColumnClickEventHandler(myListView_ColumnClick);

        // Create items and add them to myListView.
        ListViewItem item0 = new ListViewItem( new string[] 
            {"Programming Windows", 
            "Petzold, Charles", 
            "1998"} );
        ListViewItem item1 = new ListViewItem( new string[] 
            {"Code: The Hidden Language of Computer Hardware and Software", 
            "Petzold, Charles", 
            "2000"} );
        ListViewItem item2 = new ListViewItem( new string[] 
            {"Programming Windows with C#", 
            "Petzold, Charles", 
            "2001"} );
        ListViewItem item3 = new ListViewItem( new string[] 
            {"Coding Techniques for Microsoft Visual Basic .NET", 
            "Connell, John", 
            "2001"} );
        ListViewItem item4 = new ListViewItem( new string[] 
            {"C# for Java Developers", 
            "Jones, Allen & Freeman, Adam", 
            "2002"} );
        ListViewItem item5 = new ListViewItem( new string[] 
            {"Microsoft .NET XML Web Services Step by Step", 
            "Jones, Allen & Freeman, Adam", 
            "2002"} );
        myListView.Items.AddRange(
            new ListViewItem[] {item0, item1, item2, item3, item4, item5});

        if (isRunningXPOrLater)
        {
            // Create the groupsTable array and populate it with one 
            // hash table for each column.
            groupTables = new Hashtable[myListView.Columns.Count];
            for (int column = 0; column < myListView.Columns.Count; column++)
            {
                // Create a hash table containing all the groups 
                // needed for a single column.
                groupTables[column] = CreateGroupsTable(column);
            }

            // Start with the groups created for the Title column.
            SetGroups(0);
        }

        // Initialize the form.
        this.Controls.Add(myListView);
        this.Size = new System.Drawing.Size(550, 330);
        this.Text = "ListView Groups Example";
    }

    [STAThread]
    static void Main() 
    {
        Application.EnableVisualStyles();
        Application.Run(new ListViewGroupsExample());
    }

    // Groups the items using the groups created for the clicked 
    // column.
    private void myListView_ColumnClick(
        object sender, ColumnClickEventArgs e)
    {
        // Set the sort order to ascending when changing
        // column groups; otherwise, reverse the sort order.
        if ( myListView.Sorting == SortOrder.Descending || 
            ( isRunningXPOrLater && (e.Column != groupColumn) ) )
        {
            myListView.Sorting = SortOrder.Ascending;
        }
        else 
        {
            myListView.Sorting = SortOrder.Descending;
        }
        groupColumn = e.Column;

        // Set the groups to those created for the clicked column.
        if (isRunningXPOrLater)
        {
            SetGroups(e.Column);
        }
    }

    // Sets myListView to the groups created for the specified column.
    private void SetGroups(int column)
    {
        // Remove the current groups.
        myListView.Groups.Clear();

        // Retrieve the hash table corresponding to the column.
        Hashtable groups = (Hashtable)groupTables[column];

        // Copy the groups for the column to an array.
        ListViewGroup[] groupsArray = new ListViewGroup[groups.Count];
        groups.Values.CopyTo(groupsArray, 0);

        // Sort the groups and add them to myListView.
        Array.Sort(groupsArray, new ListViewGroupSorter(myListView.Sorting));
        myListView.Groups.AddRange(groupsArray);

        // Iterate through the items in myListView, assigning each 
        // one to the appropriate group.
        foreach (ListViewItem item in myListView.Items)
        {
            // Retrieve the subitem text corresponding to the column.
            string subItemText = item.SubItems[column].Text;

            // For the Title column, use only the first letter.
            if (column == 0) 
            {
                subItemText = subItemText.Substring(0, 1);
            }

            // Assign the item to the matching group.
            item.Group = (ListViewGroup)groups[subItemText];
        }
    }

    // Creates a Hashtable object with one entry for each unique
    // subitem value (or initial letter for the parent item)
    // in the specified column.
    private Hashtable CreateGroupsTable(int column)
    {
        // Create a Hashtable object.
        Hashtable groups = new Hashtable();

        // Iterate through the items in myListView.
        foreach (ListViewItem item in myListView.Items)
        {
            // Retrieve the text value for the column.
            string subItemText = item.SubItems[column].Text;

            // Use the initial letter instead if it is the first column.
            if (column == 0) 
            {
                subItemText = subItemText.Substring(0, 1);
            }

            // If the groups table does not already contain a group
            // for the subItemText value, add a new group using the 
            // subItemText value for the group header and Hashtable key.
            if (!groups.Contains(subItemText))
            {
                groups.Add( subItemText, new ListViewGroup(subItemText, 
                    HorizontalAlignment.Left) );
            }
        }

        // Return the Hashtable object.
        return groups;
    }

    // Sorts ListViewGroup objects by header value.
    private class ListViewGroupSorter : IComparer
    {
        private SortOrder order;

        // Stores the sort order.
        public ListViewGroupSorter(SortOrder theOrder) 
        { 
            order = theOrder;
        }

        // Compares the groups by header value, using the saved sort
        // order to return the correct value.
        public int Compare(object x, object y)
        {
            int result = String.Compare(
                ((ListViewGroup)x).Header,
                ((ListViewGroup)y).Header
            );
            if (order == SortOrder.Ascending)
            {
                return result;
            }
            else 
            {
                return -result;
            }
        }
    }
}

Imports System.Collections
Imports System.Windows.Forms

Public Class ListViewGroupsExample
    Inherits Form

    Private myListView As ListView

    ' Determine whether Windows XP or a later
    ' operating system is present.
    Private isRunningXPOrLater As Boolean = _
        OSFeature.Feature.IsPresent(OSFeature.Themes)
    
    ' Declare a Hashtable array in which to store the groups.
    Private groupTables() As Hashtable
    
    ' Declare a variable to store the current grouping column.
    Private groupColumn As Integer = 0
    
    Public Sub New()
        ' Initialize myListView.
        myListView = New ListView()
        myListView.Dock = DockStyle.Fill
        myListView.View = View.Details
        myListView.Sorting = SortOrder.Ascending
        
        ' Create and initialize column headers for myListView.
        Dim columnHeader0 As New ColumnHeader()
        columnHeader0.Text = "Title"
        columnHeader0.Width = -1
        Dim columnHeader1 As New ColumnHeader()
        columnHeader1.Text = "Author"
        columnHeader1.Width = -1
        Dim columnHeader2 As New ColumnHeader()
        columnHeader2.Text = "Year"
        columnHeader2.Width = -1
        
        ' Add the column headers to myListView.
        myListView.Columns.AddRange( New ColumnHeader() _
            {columnHeader0, columnHeader1, columnHeader2} )
        
        ' Add a handler for the ColumnClick event.
        AddHandler myListView.ColumnClick, AddressOf myListView_ColumnClick
        
        ' Create items and add them to myListView.
        Dim item0 As New ListViewItem( New String() _
            {"Programming Windows", _
            "Petzold, Charles", _
            "1998"} )
        Dim item1 As New ListViewItem( New String() _
            {"Code: The Hidden Language of Computer Hardware and Software", _
            "Petzold, Charles", _
            "2000"} )
        Dim item2 As New ListViewItem( New String() _
            {"Programming Windows with C#", _
            "Petzold, Charles", _
            "2001"} )
        Dim item3 As New ListViewItem( New String() _
            {"Coding Techniques for Microsoft Visual Basic .NET", _
            "Connell, John", _
            "2001"} )
        Dim item4 As New ListViewItem( New String() _
            {"C# for Java Developers", _
            "Jones, Allen / Freeman, Adam", _
            "2002"} )
        Dim item5 As New ListViewItem( New String() _
            {"Microsoft .NET XML Web Services Step by Step", _
            "Jones, Allen / Freeman, Adam", _
            "2002"} )
        myListView.Items.AddRange( _
            New ListViewItem() {item0, item1, item2, item3, item4, item5})
        
        If isRunningXPOrLater
            ' Create the groupsTable array and populate it with one 
            ' hash table for each column.
            groupTables = New Hashtable(myListView.Columns.Count) {}
            Dim column As Integer
            For column = 0 To myListView.Columns.Count - 1
                ' Create a hash table containing all the groups 
                ' needed for a single column.
                groupTables(column) = CreateGroupsTable(column)
            Next column
            
            ' Start with the groups created for the Title column.
            SetGroups(0)
        End If
        
        ' Initialize the form.
        Me.Controls.Add(myListView)
        Me.Size = New System.Drawing.Size(550, 330)
        Me.Text = "ListView Groups Example"
    End Sub
    
    <STAThread()> _
    Shared Sub Main()
        Application.EnableVisualStyles()
        Application.Run(New ListViewGroupsExample())
    End Sub
    
    ' Groups the items using the groups created for the clicked 
    ' column.
    Private Sub myListView_ColumnClick( _
        sender As Object, e As ColumnClickEventArgs)

        ' Set the sort order to ascending when changing
        ' column groups; otherwise, reverse the sort order.
        If myListView.Sorting = SortOrder.Descending OrElse _
            isRunningXPOrLater And e.Column <> groupColumn Then
            myListView.Sorting = SortOrder.Ascending
        Else
            myListView.Sorting = SortOrder.Descending
        End If
        groupColumn = e.Column
        
        ' Set the groups to those created for the clicked column.
        If isRunningXPOrLater Then
            SetGroups(e.Column)
        End If
    End Sub
    
    ' Sets myListView to the groups created for the specified column.
    Private Sub SetGroups(column As Integer)
        ' Remove the current groups.
        myListView.Groups.Clear()
        
        ' Retrieve the hash table corresponding to the column.
        Dim groups As Hashtable = CType(groupTables(column), Hashtable)
        
        ' Copy the groups for the column to an array.
        Dim groupsArray(groups.Count - 1) As ListViewGroup
        groups.Values.CopyTo(groupsArray, 0)
        
        ' Sort the groups and add them to myListView.
        Array.Sort(groupsArray, New ListViewGroupSorter(myListView.Sorting))
        myListView.Groups.AddRange(groupsArray)
        
        ' Iterate through the items in myListView, assigning each 
        ' one to the appropriate group.
        Dim item As ListViewItem
        For Each item In myListView.Items
            ' Retrieve the subitem text corresponding to the column.
            Dim subItemText As String = item.SubItems(column).Text
            
            ' For the Title column, use only the first letter.
            If column = 0 Then
                subItemText = subItemText.Substring(0, 1)
            End If 

            ' Assign the item to the matching group.
            item.Group = CType(groups(subItemText), ListViewGroup)
        Next item
    End Sub

    ' Creates a Hashtable object with one entry for each unique
    ' subitem value (or initial letter for the parent item)
    ' in the specified column.
    Private Function CreateGroupsTable(column As Integer) As Hashtable
        ' Create a Hashtable object.
        Dim groups As New Hashtable()
        
        ' Iterate through the items in myListView.
        Dim item As ListViewItem
        For Each item In myListView.Items
            ' Retrieve the text value for the column.
            Dim subItemText As String = item.SubItems(column).Text
            
            ' Use the initial letter instead if it is the first column.
            If column = 0 Then
                subItemText = subItemText.Substring(0, 1)
            End If 

            ' If the groups table does not already contain a group
            ' for the subItemText value, add a new group using the 
            ' subItemText value for the group header and Hashtable key.
            If Not groups.Contains(subItemText) Then
                groups.Add( subItemText, New ListViewGroup(subItemText, _
                    HorizontalAlignment.Left) )
            End If
        Next item
        
        ' Return the Hashtable object.
        Return groups
    End Function 'CreateGroupsTable

    ' Sorts ListViewGroup objects by header value.
    Private Class ListViewGroupSorter
        Implements IComparer 
        
        Private order As SortOrder
        
        ' Stores the sort order.
        Public Sub New(theOrder As SortOrder)
            order = theOrder
        End Sub
        
        ' Compares the groups by header value, using the saved sort
        ' order to return the correct value.
        Public Function Compare(x As Object, y As Object) As Integer _
            Implements IComparer.Compare
            Dim result As Integer = String.Compare( _
                CType(x, ListViewGroup).Header, _
                CType(y, ListViewGroup).Header )
            If order = SortOrder.Ascending Then
                Return result
            Else
                Return -result
            End If
        End Function 'Compare
    End Class

End Class

Hinweise

Verwenden Sie die ListView.Groups -Eigenschaft, um die abzurufen, die ListViewGroupCollection einem ListView Steuerelement zugeordnet ist. Diese Auflistung enthält die ListViewGroup -Objekte, die die im -Steuerelement angezeigten Gruppen darstellen, wenn die ListView.View -Eigenschaft auf einen anderen Wert als View.Listfestgelegt ist. Alle Elemente, die keiner Gruppe zugewiesen sind, werden in der Standardgruppe angezeigt, die die Headerbezeichnung "DefaultGroup{0}" aufweist. Die Standardgruppe ist nicht in der ListView.Groups Auflistung enthalten und kann nicht geändert werden. Es ist in erster Linie beim Debuggen nützlich, um sicherzustellen, dass alle Elemente ordnungsgemäß zu Gruppen hinzugefügt wurden. Wenn keine Gruppen in der ListView.Groups Auflistung vorhanden sind, ist die Gruppierungsfunktion deaktiviert.

Verwenden Sie die Add -Methode, um der Auflistung eine einzelne Gruppe hinzuzufügen. Verwenden Sie die Insert -Methode, um eine Gruppe an einem bestimmten Index innerhalb der Auflistung hinzuzufügen. Verwenden Sie die Remove -Methode, um eine Gruppe zu entfernen. Verwenden Sie die RemoveAt -Methode, um die Gruppe an einem bestimmten Index zu entfernen.

Sie können der Auflistung nicht mehr als einmal hinzufügen ListViewGroup . Um eine Gruppe innerhalb der Auflistung neu zu positionieren, muss sie zuerst aus der Auflistung entfernt und dann an der gewünschten Position eingefügt werden. Verwenden Sie die Contains -Methode, um zu bestimmen, ob sich eine bestimmte Gruppe bereits in der Auflistung befindet. Verwenden Sie IndexOf die -Methode, um den Index einer Gruppe innerhalb der Auflistung abzurufen. Sie können die Gruppe mit dem Item[] Indexer auf einen bestimmten Index abrufen oder festlegen.

Verwenden Sie die AddRange -Methode, um der Auflistung mehrere Gruppen hinzuzufügen. Sie können mehrere Gruppen entweder als Array von Gruppen oder als eine ListViewGroupCollection hinzufügen, die Sie über die ListView.Groups -Eigenschaft eines anderen ListView Steuerelements abrufen. Verwenden Sie die Clear -Methode, um alle Gruppen aus der Auflistung zu entfernen.

Die AddRange Methoden und Clear sind nützlich, wenn Sie mehrere Möglichkeiten zum Gruppieren der Elemente in einem ListView Steuerelement bereitstellen möchten. Erstellen Sie dazu mehrere Gruppenarrays. Um die Gruppierung zu ändern, verwenden Sie zunächst die Clear -Methode, um alle Gruppen aus der Auflistung zu entfernen, und verwenden Sie dann die AddRange -Methode, um das nächste Anzuzeigende Array von Gruppen hinzuzufügen.

Verwenden Sie die CopyTo -Methode, um die Gruppen in einer Auflistung ab einem angegebenen Index in ein kompatibles Array zu kopieren. Dies ist z. B. nützlich, wenn Sie die Gruppen in der Auflistung mithilfe der Array.Sort -Methode sortieren möchten. Kopieren Sie dazu die Gruppen in ein kompatibles Array, und sortieren Sie dann das Array. Verwenden Sie als Nächstes die Clear -Methode, um alle Gruppen aus der Auflistung zu entfernen, und verwenden Sie dann die AddRange -Methode, um das sortierte Array wieder der Auflistung hinzuzufügen.

Verwenden Sie die Count -Eigenschaft, um zu bestimmen, wie viele Gruppen sich in der Auflistung befinden. Um die Auflistung zu durchlaufen, verwenden Sie die IEnumerator von der GetEnumerator -Methode zurückgegebene.

Eigenschaften

Methoden

Explizite Schnittstellenimplementierungen

Erweiterungsmethoden

Gilt für:

Weitere Informationen

• ListView
• ListViewGroup