ListView.SelectedIndexCollection Classe

Definizione

public: ref class ListView::SelectedIndexCollection : System::Collections::IList

public class ListView.SelectedIndexCollection : System.Collections.IList

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

type ListView.SelectedIndexCollection = class
    interface IList
    interface ICollection
    interface IEnumerable

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

Public Class ListView.SelectedIndexCollection
Implements IList

Ereditarietà

Object

ListView.SelectedIndexCollection

Attributi

ListBindableAttribute

Implementazioni

ICollection IEnumerable IList

Esempio

Nell'esempio di codice seguente viene illustrato come usare i SelectedIndicesmembri , SelectedIndexChangede e HeaderStyle la ListView.SelectedIndexCollection classe . Per eseguire questo esempio, incollare il codice seguente in un modulo contenente un ListView oggetto denominato e un ListView1 oggetto denominato TextBoxTextBox1 . Chiamare il InitializeListView metodo dal costruttore o Load dal gestore eventi del form. Questo esempio richiede che il gestore eventi sia associato correttamente all'evento SelectedIndexChanged .

// This method adds two columns to the ListView, setting the Text 
// and TextAlign, and Width properties of each ColumnHeader.  The 
// HeaderStyle property is set to NonClickable since the ColumnClick 
// event is not handled.  Finally the method adds ListViewItems and 
// SubItems to each column.
void InitializeListView()
{
   this->ListView1 = gcnew System::Windows::Forms::ListView;
   this->ListView1->BackColor = System::Drawing::SystemColors::Control;
   this->ListView1->Dock = System::Windows::Forms::DockStyle::Top;
   this->ListView1->Location = System::Drawing::Point( 0, 0 );
   this->ListView1->Name = "ListView1";
   this->ListView1->Size = System::Drawing::Size( 292, 130 );
   this->ListView1->TabIndex = 0;
   this->ListView1->View = System::Windows::Forms::View::Details;
   this->ListView1->MultiSelect = true;
   this->ListView1->HideSelection = false;
   this->ListView1->HeaderStyle = ColumnHeaderStyle::Nonclickable;
   ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
   columnHeader1->Text = "Breakfast Item";
   columnHeader1->TextAlign = HorizontalAlignment::Left;
   columnHeader1->Width = 146;
   ColumnHeader^ columnHeader2 = gcnew ColumnHeader;
   columnHeader2->Text = "Price Each";
   columnHeader2->TextAlign = HorizontalAlignment::Center;
   columnHeader2->Width = 142;
   this->ListView1->Columns->Add( columnHeader1 );
   this->ListView1->Columns->Add( columnHeader2 );
   array<String^>^foodList = {"Juice","Coffee","Cereal & Milk","Fruit Plate","Toast & Jelly","Bagel & Cream Cheese"};
   array<String^>^foodPrice = {"1.09","1.09","2.19","2.49","1.49","1.49"};
   for ( int count = 0; count < foodList->Length; count++ )
   {
      ListViewItem^ listItem = gcnew ListViewItem( foodList[ count ] );
      listItem->SubItems->Add( foodPrice[ count ] );
      ListView1->Items->Add( listItem );

   }
   this->Controls->Add( ListView1 );
}

  // This method adds two columns to the ListView, setting the Text 
  // and TextAlign, and Width properties of each ColumnHeader.  The 
  // HeaderStyle property is set to NonClickable since the ColumnClick 
  // event is not handled.  Finally the method adds ListViewItems and 
  // SubItems to each column.
  private void InitializeListView()
  {
      this.ListView1 = new System.Windows.Forms.ListView();
      this.ListView1.BackColor = System.Drawing.SystemColors.Control;
      this.ListView1.Dock = System.Windows.Forms.DockStyle.Top;
      this.ListView1.Location = new System.Drawing.Point(0, 0);
      this.ListView1.Name = "ListView1";
      this.ListView1.Size = new System.Drawing.Size(292, 130);
      this.ListView1.TabIndex = 0;
      this.ListView1.View = System.Windows.Forms.View.Details;
      this.ListView1.MultiSelect = true;
      this.ListView1.HideSelection = false;
      this.ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable;
      
      ColumnHeader columnHeader1 = new ColumnHeader();
      columnHeader1.Text = "Breakfast Item";
      columnHeader1.TextAlign = HorizontalAlignment.Left;
      columnHeader1.Width = 146;

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

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

      string[] foodList = new string[]{"Juice", "Coffee", 
          "Cereal & Milk", "Fruit Plate", "Toast & Jelly", 
          "Bagel & Cream Cheese"};
      string[] foodPrice = new string[]{"1.09", "1.09", "2.19", 
          "2.49", "1.49", "1.49"};
      
      for(int count=0; count < foodList.Length; count++)
      {
          ListViewItem listItem = new ListViewItem(foodList[count]);
          listItem.SubItems.Add(foodPrice[count]);
          ListView1.Items.Add(listItem);
      }
      this.Controls.Add(ListView1);
  }

' This method adds two columns to the ListView, setting the Text 
' and TextAlign, and Width properties of each ColumnHeader.  The 
' HeaderStyle property is set to NonClickable since the ColumnClick 
' event is not handled.  Finally the method adds ListViewItems and 
' SubItems to each column.
Private Sub InitializeListView()
    Me.ListView1 = New System.Windows.Forms.ListView
    Me.ListView1.BackColor = System.Drawing.SystemColors.Control
    Me.ListView1.Dock = System.Windows.Forms.DockStyle.Top
    Me.ListView1.Location = New System.Drawing.Point(0, 0)
    Me.ListView1.Name = "ListView1"
    Me.ListView1.Size = New System.Drawing.Size(292, 130)
    Me.ListView1.TabIndex = 0
    Me.ListView1.View = System.Windows.Forms.View.Details
    Me.ListView1.MultiSelect = True
    Me.ListView1.HideSelection = False
    ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable
    Dim columnHeader1 As New ColumnHeader
    With columnHeader1
        .Text = "Breakfast Item"
        .TextAlign = HorizontalAlignment.Left
        .Width = 146
    End With
    Dim columnHeader2 As New ColumnHeader
    With columnHeader2
        .Text = "Price Each"
        .TextAlign = HorizontalAlignment.Center
        .Width = 142
    End With

    Me.ListView1.Columns.Add(columnHeader1)
    Me.ListView1.Columns.Add(columnHeader2)
    Dim foodList() As String = New String() {"Juice", "Coffee", _
        "Cereal & Milk", "Fruit Plate", "Toast & Jelly", _
        "Bagel & Cream Cheese"}
    Dim foodPrice() As String = New String() {"1.09", "1.09", _
        "2.19", "2.49", "1.49", "1.49"}
    Dim count As Integer
    For count = 0 To foodList.Length - 1
        Dim listItem As New ListViewItem(foodList(count))
        listItem.SubItems.Add(foodPrice(count))
        ListView1.Items.Add(listItem)
    Next
    Me.Controls.Add(Me.ListView1)
End Sub

// Uses the SelectedIndices property to retrieve and tally the  
// price of the selected menu items.
void ListView1_SelectedIndexChanged_UsingIndices( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   ListView::SelectedIndexCollection^ indexes = this->ListView1->SelectedIndices;
   double price = 0.0;
   System::Collections::IEnumerator^ myEnum1 = indexes->GetEnumerator();
   while ( myEnum1->MoveNext() )
   {
      int index = safe_cast<int>(myEnum1->Current);
      price += Double::Parse( this->ListView1->Items[ index ]->SubItems[ 1 ]->Text );
   }

   
   // Output the price to TextBox1.
   TextBox1->Text = price.ToString();
}

// Uses the SelectedIndices property to retrieve and tally the  
// price of the selected menu items.
private void ListView1_SelectedIndexChanged_UsingIndices(
    object sender, System.EventArgs e)
{

    ListView.SelectedIndexCollection indexes = 
        this.ListView1.SelectedIndices;
    
    double price = 0.0;
    foreach ( int index in indexes )
    {
        price += Double.Parse(
            this.ListView1.Items[index].SubItems[1].Text);
    }

    // Output the price to TextBox1.
    TextBox1.Text =  price.ToString();
}

' Uses the SelectedIndices property to retrieve and tally the price of  
' the selected menu items.
Private Sub ListView1_SelectedIndexChanged_UsingIndices _
    (ByVal sender As Object, ByVal e As System.EventArgs) _
    Handles ListView1.SelectedIndexChanged

    Dim indexes As ListView.SelectedIndexCollection = _
        Me.ListView1.SelectedIndices
    Dim index As Integer
    Dim price As Double = 0.0
    For Each index In indexes
        price += Double.Parse(Me.ListView1.Items(index).SubItems(1).Text)
    Next

    ' Output the price to TextBox1.
    TextBox1.Text = CType(price, String)
End Sub

Commenti

Un ListView.SelectedIndexCollection oggetto archivia gli indici agli elementi selezionati in un ListView controllo . Gli indici archiviati in ListView.SelectedIndexCollection sono posizioni di indice all'interno di ListView.ListViewItemCollection. Archivia ListView.ListViewItemCollection tutti gli elementi visualizzati nel ListView controllo .

Nella tabella seguente viene illustrato un esempio di come archivia ListView.ListViewItemCollection gli elementi di ListView e ne mostra gli stati di selezione in un esempio ListView.

In base all'esempio ListView.ListViewItemCollection nella tabella precedente, nella tabella seguente viene illustrato come verrebbe visualizzato .ListView.SelectedIndexCollection

È possibile utilizzare le proprietà e i metodi di questa classe per eseguire un'ampia gamma di attività con la raccolta. Il Contains metodo consente di determinare se una posizione di indice da ListView.ListViewItemCollection è uno degli indici archiviati in ListView.SelectedIndexCollection. Dopo aver rilevato che l'elemento si trova nell'insieme, è possibile utilizzare il IndexOf metodo per determinare la posizione dell'indice nell'oggetto ListView.SelectedIndexCollection.