Question

i have following Query

select * from DATABASE.dbo.Rooms r
where not exists
    (select * from DATABASE.dbo.Reservation
        where RoomNo = r.RoomNo
        and DateStart <= 'Textbox2.text'
        and DateEnd >= 'Textbox1.text')

the label should display all the rooms available and its details.how can i Show table field data on label control

Answer 1

It’s hard to know where to start, here…

First of all, understand the difference between C# and SQL. Your SQL statement makes no sense. Use parameterized queries. Use parameterized queries! Use parameterized queries!

string query = "select * from DATABASE.dbo.Rooms r "+
               "where not exists "+
               "(select * from DATABASE.dbo.Reservation "+
               "          where RoomNo = r.RoomNo "+
               "          and DateStart <= @endDate "+
               "          and DateEnd >= @startDate)"

This is your SQL query. Now call it from C#:

using (SqlCommand cmd = new SqlCommand(query, connection);
{
    // Assign parameters. I assume that you have DateTimePickers instead
    // of text boxes.
    cmd.Parameters.AddWithValue("@startDate", datePicker1.Date);           
    cmd.Parameters.AddWithValue("@endDate", datePicker2.Date);

    using (SqlDataReader reader = cmd.ExecuteReader())
    {
        // Read all data into string builder (field name must be changed)
        StringBuilder sb = new StringBuilder();
        while (reader.Read())
          sb.Append(reader["FieldName"].ToString());

        // Assign this to label
        label1.Text = sb.ToString();
    }
}