ListView.CheckedItems Propriété
Définition
Important
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Obtient les éléments qui sont activés dans le contrôle.
public:
property System::Windows::Forms::ListView::CheckedListViewItemCollection ^ CheckedItems { System::Windows::Forms::ListView::CheckedListViewItemCollection ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Windows.Forms.ListView.CheckedListViewItemCollection CheckedItems { get; }
[<System.ComponentModel.Browsable(false)>]
member this.CheckedItems : System.Windows.Forms.ListView.CheckedListViewItemCollection
Public ReadOnly Property CheckedItems As ListView.CheckedListViewItemCollection
Valeur de propriété
ListView.CheckedListViewItemCollection qui contient les éléments activés. Si aucun élément n'est activé, un ListView.CheckedListViewItemCollection vide est retourné.
- Attributs
Exemples
L’exemple de code suivant illustre un vérifié ListView qui gère l’événement ItemChecked . L’exemple utilise la CheckedItems propriété pour effectuer le décompte d’un nouveau prix chaque fois qu’un élément est coché ou décoché. Pour exécuter cet exemple, collez le code suivant dans un formulaire qui contient un ListView nommé ListView1
et un TextBox nommé Textbox1
. Appelez la InitializeListView
méthode à partir du constructeur ou Load
de la méthode du formulaire.
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.
ListView1->BeginUpdate();
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.
ListView1->EndUpdate();
this->Controls->Add( this->ListView1 );
}
private void InitializeListView()
{
this.ListView1 = new 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 = new System.Drawing.Point(0, 0);
this.ListView1.Size = new 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 = new ColumnHeader();
columnHeader1.Text = "Breakfast Choices";
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",
"2.79", "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.
ListView1.BeginUpdate();
for(count = 0; count < foodList.Length; count++)
{
ListViewItem listItem = new ListViewItem(foodList[count]);
listItem.SubItems.Add(foodPrice[count]);
ListView1.Items.Add(listItem);
}
//Call EndUpdate when you finish adding items to the ListView.
ListView1.EndUpdate();
this.Controls.Add(this.ListView1);
}
Private Sub InitializeListView()
Me.ListView1 = New System.Windows.Forms.ListView
' Set properties such as BackColor, Location and Size
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.Size = New System.Drawing.Size(292, 130)
Me.ListView1.View = System.Windows.Forms.View.Details
Me.ListView1.HideSelection = False
' Allow user to select multiple items.
Me.ListView1.MultiSelect = True
' Show check boxes in the ListView.
Me.ListView1.CheckBoxes = True
'Set the column headers and populate the columns.
ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable
Dim columnHeader1 As New ColumnHeader
With columnHeader1
.Text = "Breakfast Choices"
.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", _
"2.79", "2.09", "2.69"}
Dim count As Integer
' 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.
ListView1.BeginUpdate()
For count = 0 To foodList.Length - 1
Dim listItem As New ListViewItem(foodList(count))
listItem.SubItems.Add(foodPrice(count))
ListView1.Items.Add(listItem)
Next
'Call EndUpdate when you finish adding items to the ListView.
ListView1.EndUpdate()
Me.Controls.Add(Me.ListView1)
End Sub
// Handles the ItemChecked event. The method loops through all the
// checked items and tallies a new price each time an item is
// checked or unchecked. It outputs the price to TextBox1.
void ListView1_ItemCheck2( Object^ /*sender*/, System::Windows::Forms::ItemCheckEventArgs^ e )
{
double price = 0.0;
ListView::CheckedListViewItemCollection^ checkedItems = ListView1->CheckedItems;
System::Collections::IEnumerator^ myEnum = checkedItems->GetEnumerator();
while ( myEnum->MoveNext() )
{
ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
price += Double::Parse( item->SubItems[ 1 ]->Text );
}
if ( e->CurrentValue == CheckState::Unchecked )
{
price += Double::Parse( this->ListView1->Items[ e->Index ]->SubItems[ 1 ]->Text );
}
else
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();
}
// Handles the ItemChecked event. The method loops through all the
// checked items and tallies a new price each time an item is
// checked or unchecked. It outputs the price to TextBox1.
private void ListView1_ItemCheck2(object sender,
System.Windows.Forms.ItemCheckEventArgs e)
{
double price = 0.0;
ListView.CheckedListViewItemCollection checkedItems =
ListView1.CheckedItems;
foreach ( ListViewItem item in checkedItems )
{
price += Double.Parse(item.SubItems[1].Text);
}
if (e.CurrentValue==CheckState.Unchecked)
{
price += Double.Parse(
this.ListView1.Items[e.Index].SubItems[1].Text);
}
else 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();
}
' Handles the ItemCheck event. The method loops through all the
' checked items and tallies a new price each time an item is
' checked or unchecked. It outputs the price to TextBox1.
Private Sub ListView1_ItemCheck2(ByVal sender As Object, _
ByVal e As System.Windows.Forms.ItemCheckEventArgs) _
Handles ListView1.ItemCheck
Dim item As ListViewItem
Dim price As Double = 0.0
Dim checkedItems As ListView.CheckedListViewItemCollection = _
ListView1.CheckedItems
For Each item In checkedItems
price += Double.Parse(item.SubItems(1).Text)
Next
If (e.CurrentValue = CheckState.Unchecked) Then
price += Double.Parse(Me.ListView1.Items(e.Index).SubItems(1).Text)
ElseIf (e.CurrentValue = CheckState.Checked) Then
price -= Double.Parse(Me.ListView1.Items(e.Index).SubItems(1).Text)
End If
' Output the price to TextBox1.
TextBox1.Text = CType(price, String)
End Sub
Remarques
Cette propriété n’est utile que lorsque la CheckBoxes propriété du ListView contrôle est définie sur true
. La CheckedItems propriété retourne une collection qui contient tous les éléments qui sont archivés dans le contrôle. Pour plus d’informations sur la manipulation des éléments de la collection, consultez ListView.CheckedListViewItemCollection.
Si vous souhaitez obtenir une collection des positions d’index dans le ListView.ListViewItemCollection des éléments qui sont archivés dans le ListView contrôle, au lieu des éléments qui sont vérifiés, utilisez la CheckedIndices propriété .