BindingSource.RemoveAt(Int32) Metode

Referensi

Definisi

Ruang nama:: System.Windows.Forms

Rakitan:: System.Windows.Forms.dll

Penting

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Menghapus item pada indeks yang ditentukan dalam daftar.

public:
 virtual void RemoveAt(int index);

public virtual void RemoveAt (int index);

abstract member RemoveAt : int -> unit
override this.RemoveAt : int -> unit

Public Overridable Sub RemoveAt (index As Integer)

Parameter

index: Int32

Indeks berbasis nol dari item yang akan dihapus.

Penerapan

RemoveAt(Int32)

Pengecualian

ArgumentOutOfRangeException

index kurang dari nol atau lebih besar dari Count nilai properti .

NotSupportedException

Daftar yang mendasar yang diwakili oleh List properti bersifat baca-saja atau memiliki ukuran tetap.

Contoh

Contoh kode berikut menunjukkan Listanggota , , RemoveAtdan Count . Untuk menjalankan contoh ini, tempelkan kode ke dalam formulir yang berisi BindingSource bernama BindingSource1, dua label bernama label1 dan label2, dan tombol bernama button1. Kaitkan button1_Click metode dengan Click peristiwa untuk button1. Pengguna Visual Basic perlu menambahkan referensi ke 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

Keterangan

Kedua kondisi ini masing-masing dapat diuji dengan IsFixedSize properti dan IsReadOnly .

Metode ini meningkatkan ListChanged peristiwa.

Berlaku untuk

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