ItemCheckEventArgs::Index Property


The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

Gets the zero-based index of the item to change.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

property int Index {
	int get();

Property Value

Type: System::Int32

The zero-based index of the item to change.

You can use this property to determine which item's check box in the CheckedListBox is being changed.

The following code example demonstrates a checked ListView control that handles the ListView::ItemChecked event. The method uses the CurrentValue and Index properties of the ItemCheckEventArgs object to retrieve and tally the price of the menu items selected. To run this example paste the following code in a form containing a ListView named ListView1 and a TextBox named Textbox1. Call the InititalizeListView method from the form's constructor or Load method. Ensure all events are associated with their event-handling methods.

void InitializeListView()
   this->ListView1 = gcnew System::Windows::Forms::ListView;

   // Set properties such as BackColor and DockStyle and Location.
   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->Size = System::Drawing::Size( 292, 130 );
   this->ListView1->View = System::Windows::Forms::View::Details;
   this->ListView1->HideSelection = false;

   // Allow the user to select multiple items.
   this->ListView1->MultiSelect = true;

   // Show CheckBoxes in the ListView.
   this->ListView1->CheckBoxes = true;

   //Set the column headers and populate the columns.
   ListView1->HeaderStyle = ColumnHeaderStyle::Nonclickable;
   ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
   columnHeader1->Text = "Breakfast Choices";
   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","2.79","2.09","2.69"};
   int count;

   // Members are added one at a time, so call BeginUpdate to ensure 
   // the list is painted only once, rather than as each list item is added.
   for ( count = 0; count < foodList->Length; count++ )
      ListViewItem^ listItem = gcnew ListViewItem( foodList[ count ] );
      listItem->SubItems->Add( foodPrice[ count ] );
      ListView1->Items->Add( listItem );

   //Call EndUpdate when you finish adding items to the ListView.
   this->Controls->Add( this->ListView1 );
double price;

// Handles the ItemCheck event. The method uses the CurrentValue
// property of the ItemCheckEventArgs to retrieve and tally the  
// price of the menu items selected.  
void ListView1_ItemCheck1( Object^ /*sender*/, System::Windows::Forms::ItemCheckEventArgs^ e )
   if ( e->CurrentValue == CheckState::Unchecked )
      price += Double::Parse( this->ListView1->Items[ e->Index ]->SubItems[ 1 ]->Text );
   if ( (e->CurrentValue == CheckState::Checked) )
      price -= Double::Parse( this->ListView1->Items[ e->Index ]->SubItems[ 1 ]->Text );

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

.NET Framework
Available since 1.1
Return to top