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ListView.SelectedListViewItemCollection Class

Definition

Represents the collection of selected items in a list view control.

public: ref class ListView::SelectedListViewItemCollection : System::Collections::IList
public class ListView.SelectedListViewItemCollection : System.Collections.IList
[System.ComponentModel.ListBindable(false)]
public class ListView.SelectedListViewItemCollection : System.Collections.IList
type ListView.SelectedListViewItemCollection = class
    interface IList
    interface ICollection
    interface IEnumerable
[<System.ComponentModel.ListBindable(false)>]
type ListView.SelectedListViewItemCollection = class
    interface IList
    interface ICollection
    interface IEnumerable
Public Class ListView.SelectedListViewItemCollection
Implements IList
Inheritance
ListView.SelectedListViewItemCollection
Attributes
Implements

Examples

The following code example demonstrates using the SelectedItems, SelectedIndexChanged event, and HeaderStyle members and the ListView.SelectedListViewItemCollection class. To run this example, paste the following code in a form that contains a ListView object named ListView1 and a TextBox named TextBox1. Call the InitializeListView method from the form's constructor or the 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 SelectedItems property to retrieve and tally the price 
// of the selected menu items.
void ListView1_SelectedIndexChanged_UsingItems( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   ListView::SelectedListViewItemCollection^ breakfast = this->ListView1->SelectedItems;
   double price = 0.0;
   System::Collections::IEnumerator^ myEnum = breakfast->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
      price += Double::Parse( item->SubItems[ 1 ]->Text );
   }

   // Output the price to TextBox1.
   TextBox1->Text = price.ToString();
}
// Uses the SelectedItems property to retrieve and tally the price 
// of the selected menu items.
private void ListView1_SelectedIndexChanged_UsingItems(
    object sender, System.EventArgs e)
{

    ListView.SelectedListViewItemCollection breakfast = 
        this.ListView1.SelectedItems;
    
    double price = 0.0;
    foreach ( ListViewItem item in breakfast )
    {
        price += Double.Parse(item.SubItems[1].Text);
    }

    // Output the price to TextBox1.
    TextBox1.Text = price.ToString();
}
' Uses the SelectedItems property to retrieve and tally the price 
' of the selected menu items.
Private Sub ListView1_SelectedIndexChanged_UsingItems _
    (ByVal sender As Object, ByVal e As System.EventArgs) _
    Handles ListView1.SelectedIndexChanged

    Dim breakfast As ListView.SelectedListViewItemCollection = _
        Me.ListView1.SelectedItems
    Dim item As ListViewItem
    Dim price As Double = 0.0
    For Each item In breakfast
        price += Double.Parse(item.SubItems(1).Text)
    Next

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

Remarks

A ListView.SelectedListViewItemCollection stores the selected items in a ListView control. The items stored in the ListView.SelectedListViewItemCollection are items contained in the ListView.ListViewItemCollection. The ListView.ListViewItemCollection stores all items displayed in the ListView.

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

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.SelectedListViewItemCollection would appear.

Index Selected item in the ListViewItemCollection
0 Item2
1 Item4
2 Item5

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 item from the ListView.ListViewItemCollection class is a member of the ListView.SelectedListViewItemCollection. Once you know that the item is in the collection, you can use the IndexOf method to determine the position of the item in the ListView.SelectedListViewItemCollection.

Constructors

ListView.SelectedListViewItemCollection(ListView)

Initializes a new instance of the ListView.SelectedListViewItemCollection 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 item at the specified index within the collection.

Item[String]

Gets an item with the specified key from the collection.

Methods

Clear()

Removes all items from the collection.

Contains(ListViewItem)

Determines whether the specified item is located in the collection.

ContainsKey(String)

Determines whether an item with the specified key is contained 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 item collection.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
IndexOf(ListViewItem)

Returns the index within the collection of the specified item.

IndexOfKey(String)

Returns the index of the first occurrence of the item with the specified key.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
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.Contains(Object)

Determines whether the specified item is located in the collection.

IList.IndexOf(Object)

Returns the index, within the collection, of the specified item.

IList.Insert(Int32, Object)

Inserts an item into the collection at a specified index.

IList.IsFixedSize

Gets a value indicating whether the collection has a fixed size.

IList.Item[Int32]

Gets or sets an object from 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