從后端c＃中的gridview中刪除一行

Question

我想刪除后端的gridview行。 當我單擊delete它會從gridview刪除，但它不會從數據庫中刪除。 任何人都可以看到為什么這可能是？ 我的代碼如下：

protected void GVMyBookings_DeleteBooking(object sender, GridViewDeleteEventArgs e)
{
     string connstring = ConfigurationManager.ConnectionStrings["BookingConn"].ToString();
     SqlConnection MyConnection = new SqlConnection(connstring);

     MyConnection.Open();

     SqlDataSource SDSBooking= new SqlDataSource();
     SDSBooking.DeleteCommand = "DELETE FROM Tbl_Booking WHERE BookingID_PK = @BookingID_PK";
     SDSBooking.DeleteParameters.Add("@BookingID_PK", GVMyBookings.Rows[e.RowIndex].Cells[0].ToString());
     SDSBooking.ConnectionString = connstring;

     GVMyBookings.DataSource = SDSBooking;
     GVMyBookings.DataBind();
     MyConnection.Close();
}

gridview是：

<asp:GridView ID="GVMyBookings" runat="server" GridLines="Vertical" AllowSorting="True"
    AutoGenerateColumns="False" AutoGenerateDeleteButton="true" 
    OnRowDeleting="GVMyBookings_DeleteBooking" EmptyDataText="You have no upcoming bookings" >
    <RowStyle BackColor="#e5ecbf" />
    <Columns>
        <asp:BoundField DataField="BookingID_PK"  />
        <asp:BoundField DataField="BookingDate" HeaderText="Booking Date" 
            SortExpression="BookingDate" DataFormatString="{0:d}" />
        <asp:BoundField DataField="RoomName" HeaderText="Room Name" 
            SortExpression="RoomName" />
        <asp:BoundField DataField="StartTime" HeaderText="Start Time" 
            SortExpression="StartTime"/>
        <asp:BoundField DataField="EndTime" HeaderText="End Time" 
            SortExpression="EndTime" />
        <asp:BoundField DataField="StaffUID" HeaderText="StaffUID" 
            SortExpression="StaffUID" Visible="false" />
    </Columns>
    <HeaderStyle BackColor="#264409" Font-Bold="True" ForeColor="White" />
    <AlternatingRowStyle BackColor="White" />
</asp:GridView>

Answer 1

似乎您的查詢不正確

DELETE * FROM Tbl_Booking WHERE ID=@BookingID_PK

請改用它

DELETE FROM Tbl_Booking WHERE ID=@BookingID_PK

從此行中刪除@ symbole

SDSBooking.DeleteParameters.Add("BookingID_PK",...); 

然后針對dataSource顯式調用Delete

... 
SDSStudents.ConnectionString = connstring;
SDSStudents.Delete();
GridView1.DataSource = SDSStudents;  
...

Answer 2

從數據庫中刪除記錄的代碼序列應該是這樣的。

//Declaring the datasource.
SqlDataSource SDSBooking= new SqlDataSource();

//Providing the delete command.
SDSBooking.DeleteCommand = "DELETE FROM Tbl_Booking WHERE BookingID_PK = @BookingID_PK";

//Adding the parameter for deleting the record.
SDSBooking.DeleteParameters.Add("BookingID_PK", GVMyBookings.Rows[e.RowIndex].Cells[1].Text);

//Providing the connection string.
SDSBooking.ConnectionString = connstring;

//Executing the delete method of the SqlDataSouce. 
//It is this line that will actually delete your record.
SDSBooking.Delete();

在此之后，您可以將此數據源分配給gridview。

注意：對於GVMyBookings.Rows[e.RowIndex].Cells[1].Text ，您需要確保您的數據綁定字段位於TableCellCollection中的索引1 。

如果要在其之前生成其他列，則可能需要更改。

因為在您的情況下，將在數據綁定字段之前生成刪除按鈕。 因此刪除按鈕將位於索引0處，您的數據綁定字段* BookingID_PK *將位於索引1處。