BindingSource.Count Eigenschaft

Definition

Ruft die Gesamtzahl der Elemente in der zugrunde liegenden Liste ab und berücksichtigt den aktuellen Filter-Wert.Gets the total number of items in the underlying list, taking the current Filter value into consideration.

public:
 virtual property int Count { int get(); };
[System.ComponentModel.Browsable(false)]
public virtual int Count { get; }
member this.Count : int
Public Overridable ReadOnly Property Count As Integer

Eigenschaftswert

Die Gesamtanzahl der gefilterten Elemente in der zugrunde liegenden Liste.The total number of filtered items in the underlying list.

Implementiert

Attribute

Beispiele

Im folgenden Codebeispiel werden die Elemente List, RemoveAtund Count veranschaulicht.The following code example demonstrates the List, RemoveAt, and Count members. Fügen Sie zum Ausführen dieses Beispiels den Code in ein Formular ein, das eine BindingSource mit dem Namen BindingSource1, zwei Bezeichnungen namens label1 und label2und eine Schaltfläche mit dem Namen button1enthält.To run this example, paste the code into a form that contains a BindingSource named BindingSource1, two labels named label1 and label2, and a button named button1. Ordnen Sie die button1_Click-Methode dem Click-Ereignis für button1zu.Associate the button1_Click method with the Click event for button1. Visual Basic Benutzer müssen einen Verweis auf "System. Data. dll" hinzufügen.Visual Basic users will need to add a reference to System.Data.dll.

private void button1_Click(object sender, EventArgs e)
{
    // Create the connection string, data adapter and data table.
    SqlConnection connectionString =
         new SqlConnection("Initial Catalog=Northwind;" +
         "Data Source=localhost;Integrated Security=SSPI;");
    SqlDataAdapter customersTableAdapter =
        new SqlDataAdapter("Select * from Customers", connectionString);
    DataTable customerTable = new DataTable();

    // Fill the adapter with the contents of the customer table.
    customersTableAdapter.Fill(customerTable);

    // Set data source for BindingSource1.
    BindingSource1.DataSource = customerTable;

    // Set the label text to the number of items in the collection before
    // an item is removed.
    label1.Text = "Starting count: " + BindingSource1.Count.ToString();

    // Access the List property and remove an item.
    BindingSource1.List.RemoveAt(4);

    // Remove an item directly from the BindingSource. 
    // This is equivalent to the previous line of code.
    BindingSource1.RemoveAt(4);

    // Show the new count.
    label2.Text = "Count after removal: " + BindingSource1.Count.ToString();
}
    Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
        Handles button1.Click

        ' Create the connection string, data adapter and data table.
        Dim connectionString As New SqlConnection("Initial Catalog=Northwind;" & _
            "Data Source=localhost;Integrated Security=SSPI;")
        Dim customersTableAdapter As New SqlDataAdapter("Select * from Customers", _
            connectionString)
        Dim customerTable As New DataTable()

        ' Fill the adapter with the contents of the customer table.
        customersTableAdapter.Fill(customerTable)

        ' Set data source for BindingSource1.
        BindingSource1.DataSource = customerTable

        ' Set the label text to the number of items in the collection before
        ' an item is removed.
        label1.Text = "Starting count: " + BindingSource1.Count.ToString()

        ' Access the List property and remove an item.
        BindingSource1.List.RemoveAt(4)

        ' Remove an item directly from the BindingSource. 
        ' This is equivalent to the previous line of code.
        BindingSource1.RemoveAt(4)

        ' Show the new count.
        label2.Text = "Count after removal: " + BindingSource1.Count.ToString()

    End Sub
End Class

Hinweise

Die Count-Eigenschaft ruft die Anzahl der Elemente in der zugrunde liegenden Liste ab, die durch die List-Eigenschaft dargestellt wird, die durch den Wert der Filter-Eigenschaft geändert wird.The Count property gets the number of items in the underlying list represented by the List property as modified by the value of the Filter property.

Gilt für:

Siehe auch