BindingSource.Count Vlastnost

Definice

Obor názvů:

System.Windows.Forms

Sestavení:

System.Windows.Forms.dll

Získá celkový počet položek v podkladovém seznamu s ohledem na aktuální Filter hodnotu.

public:
 virtual property int Count { int get(); };

[System.ComponentModel.Browsable(false)]
public virtual int Count { get; }

[<System.ComponentModel.Browsable(false)>]
member this.Count : int

Public Overridable ReadOnly Property Count As Integer

Hodnota vlastnosti

Int32

Celkový počet filtrovaných položek v podkladovém seznamu.

Implementuje

Count

Atributy

BrowsableAttribute

Příklady

Následující příklad kódu ukazuje Listčleny , RemoveAta Count . Pokud chcete spustit tento příklad, vložte kód do formuláře, který obsahuje pojmenovaný BindingSourceBindingSource1, dva popisky s názvem label1 a label2a tlačítko s názvem button1. Přidružte metodu button1_Click k Click události pro button1. Uživatelé jazyka Visual Basic budou muset přidat odkaz na 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

Poznámky

Vlastnost Count získá počet položek v podkladovém seznamu reprezentovaných List vlastností upravenou hodnotou Filter vlastnosti.

Viz také

• List
• Position
• Current