如何在c#中在数据库访问和DatagridView之间进行自动同步

Question

在我的程序中，当我删除一条记录时，它从数据库访问和 DataGridView 中删除，但是当我关闭窗口并再次打开它时，记录再次出现在 DataGridView 中，虽然它从数据库访问中删除，这是我的代码：

private void button1_Click(object sender, EventArgs e)
{
    connection.Open();
    command.Connection = connection;
    string query = " delete from Hoteldb where ID= " +textBox0.Text + "";
    MessageBox.Show(query);
    command.CommandText = query;
    command.ExecuteNonQuery();
    MessageBox.Show("Guest Checked Out succesfly");
    BindGridView();
}

public void BindGridView()
{
    string strSQL = "SELECT * FROM Hoteldb";  
    OleDbCommand cmd = new OleDbCommand(strSQL, connection);
    DataTable table = new DataTable();
    OleDbDataAdapter da = new OleDbDataAdapter(cmd);
    da.Fill(table);
    dataGridView1.DataSource = table;

    connection.Close();
}

Answer 1

试试这个：

private void button1_Click(object sender, EventArgs e)
{
    int RowsAffected = 0;

    connection.Open();
    string query = "DELETE FROM Hoteldb WHERE ID=@ID";
    command = new OleDBCommand(query);
    command.Connection = connection;

    cmd.Parameters.Add(new OleDbParameter("@ID", OleDbType.WChar, 150, "ID"));
    cmd.Parameters["@ID"].Value = textBox0.Text.Trim()
    RowsAffected = command.ExecuteNonQuery();
    if(RowsAffected > 0)
    {
        MessageBox.Show("Guest Checked Out succesfly");
        BindGridView();
    }
    else
    {
        MessageBox.Show("There was nothing to be deleted");
    }
}

public void BindGridView()
{
    connection.Open();
    string strSQL = "SELECT * FROM Hoteldb";  
    cmd = new OleDbCommand(strSQL);
    cmd.Connection = connection;

    OleDbDataAdapter da = new OleDbDataAdapter(cmd);
    DataSet ds = new DataSet();
    da.Fill(ds, "Hoteldb");
    dataGridView1.DataSource = ds.Tables["Hoteldb"].DefaultView

    connection.Close();
}