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ListView.SelectedIndexCollection Class

Definition

Represents the collection that contains the indexes to the selected items in a ListView control.

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
Inheritance
ListView.SelectedIndexCollection
Attributes
Implements

Examples

The following code example demonstrates how to use the SelectedIndices, SelectedIndexChanged, and HeaderStyle members and the ListView.SelectedIndexCollection class. To run this example, paste the following code into a form that contains a ListView object named ListView1 and a TextBox named TextBox1. Call the InitializeListView method from the form's constructor or Load event handler. This example requires that the event handler is correctly associated with the SelectedIndexChanged event.

// 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

Remarks

A ListView.SelectedIndexCollection stores the indexes to the selected items in a ListView control. The indexes stored in the ListView.SelectedIndexCollection are index positions within the ListView.ListViewItemCollection. The ListView.ListViewItemCollection stores all items displayed in the ListView control.

The following table shows an example of how the ListView.ListViewItemCollection stores the items of the ListView and shows their selection states in an example ListView.

Index Item Selection state in the ListView
0 Item1 Unselected
1 Item2 Selected
2 Item3 Unselected
3 Item4 Selected
4 Item5 Selected

Based on the ListView.ListViewItemCollection example in the previous table, the following table demonstrates how the ListView.SelectedIndexCollection would appear.

Index Index of selected item in the ListViewItemCollection
0 1
1 3
2 4

You can use the properties and methods of this class to perform a variety of tasks with the collection. The Contains method enables you to determine whether an index position from the ListView.ListViewItemCollection is one of the indexes stored in the ListView.SelectedIndexCollection. Once you know that the item is in the collection, you can use the IndexOf method to determine the position of the index in the ListView.SelectedIndexCollection.

Constructors

ListView.SelectedIndexCollection(ListView)

Initializes a new instance of the ListView.SelectedIndexCollection class.

Properties

Count

Gets the number of items in the collection.

IsReadOnly

Gets a value indicating whether the collection is read-only.

Item[Int32]

Gets the index value at the specified index within the collection.

Methods

Add(Int32)

Adds the item at the specified index in the Items array to the collection.

Clear()

Clears the items in the collection.

Contains(Int32)

Determines whether the specified index is located in the collection.

CopyTo(Array, Int32)

Copies the entire collection into an existing array at a specified location within the array.

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetEnumerator()

Returns an enumerator that can be used to iterate through the selected index collection.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
IndexOf(Int32)

Returns the index within the ListView.SelectedIndexCollection of the specified index from the ListView.ListViewItemCollection of the ListView control.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
Remove(Int32)

Removes the item at the specified index in the Items collection from the ListView.SelectedIndexCollection.

ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

ICollection.IsSynchronized

Gets a value indicating whether access to the collection is synchronized (thread safe).

ICollection.SyncRoot

Gets an object that can be used to synchronize access to the collection of controls.

IList.Add(Object)

Adds an item to the collection.

IList.Clear()

Removes all items from the collection.

IList.Contains(Object)

Determines whether the specified item is located in the collection.

IList.IndexOf(Object)

This API supports the product infrastructure and is not intended to be used directly from your code.

Returns the index in the ListView.SelectedIndexCollection. The ListView.SelectedIndexCollection contains the indexes of selected items in the ListView.ListViewItemCollection of the ListView control.

IList.Insert(Int32, Object)

Inserts an item into the collection at a specified index.

IList.IsFixedSize

Gets a value indicating whether the ListView.SelectedIndexCollection has a fixed size.

IList.Item[Int32]

Gets or sets an object in the collection.

IList.Remove(Object)

Removes the first occurrence of a specified item from the collection.

IList.RemoveAt(Int32)

Removes an item from the collection at a specified index.

Extension Methods

Cast<TResult>(IEnumerable)

Casts the elements of an IEnumerable to the specified type.

OfType<TResult>(IEnumerable)

Filters the elements of an IEnumerable based on a specified type.

AsParallel(IEnumerable)

Enables parallelization of a query.

AsQueryable(IEnumerable)

Converts an IEnumerable to an IQueryable.

Applies to