删除行从选择GridView和数据库

Question

我试图从GridView和数据库中删除的行... 如果delte的LinkBut​​ton被点击GridView中的应删除.. 我刚开行指标如下：

protected void LinkButton1_Click(object sender, EventArgs e) 
{ 
    LinkButton btn = (LinkButton)sender; 
    GridViewRow row = (GridViewRow)btn.NamingContainer; 
    if (row != null) 
    { 
    LinkButton LinkButton1 = (LinkButton)sender; 

    // Get reference to the row that hold the button 
    GridViewRow gvr = (GridViewRow)LinkButton1.NamingContainer; 

    // Get row index from the row 
    int rowIndex = gvr.RowIndex; 
    string str = rowIndex.ToString(); 
    //string str = GridView1.DataKeys[row.RowIndex].Value.ToString(); 
    RemoveData(str); //call the delete method 

    } 
} 

现在我想删除它.​​..所以我有这个代码的问题..我得到一个错误

必须声明标量变量“@original_MachineGroupName” ...任何建议

private void RemoveData(string item) 
{ 
    SqlConnection conn = new SqlConnection(@"Data Source=JAGMIT-PC\SQLEXPRESS; 
    Initial Catalog=SumooHAgentDB;Integrated Security=True"); 
    string sql = "DELETE FROM [MachineGroups] WHERE [MachineGroupID] = 
       @original_MachineGroupID; 
    SqlCommand cmd = new SqlCommand(sql, conn); 
    cmd.Parameters.AddWithValue("@original_MachineGroupID", item); 

    conn.Open(); 

    cmd.ExecuteNonQuery(); 
    conn.Close(); 
} 

块引用

<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
    ConnectionString="<%$ ConnectionStrings:SumooHAgentDBConnectionString %>" 
    SelectCommand="SELECT MachineGroups.MachineGroupID, MachineGroups.MachineGroupName, 
    MachineGroups.MachineGroupDesc, MachineGroups.TimeAdded, 
    MachineGroups.CanBeDeleted, COUNT(Machines.MachineName) AS Expr1, 
    DATENAME(month, (MachineGroups.TimeAdded - 599266080000000000)/864000000000) + 
    SPACE(1) + DATENAME(d, (MachineGroups.TimeAdded - 599266080000000000)/
    864000000000) + 
    ', ' + DATENAME(year, (MachineGroups.TimeAdded - 599266080000000000)/
    864000000000) AS Expr2 FROM MachineGroups FULL OUTER JOIN Machines ON 
    Machines.MachineGroupID = MachineGroups.MachineGroupID GROUP BY 
    MachineGroups.MachineGroupID, MachineGroups.MachineGroupName, 
    MachineGroups.MachineGroupDesc, MachineGroups.TimeAdded, 
    MachineGroups.CanBeDeleted" 
    DeleteCommand="DELETE FROM [MachineGroups] WHERE 
        [MachineGroupID] =@original_MachineGroupID" > 
     <DeleteParameters> 
      <asp:Parameter Name="@original_MachineGroupID" Type="Int16" /> 
      <asp:Parameter Name="@original_MachineGroupName" Type="String" /> 
      <asp:Parameter Name="@original_MachineGroupDesc" Type="String" /> 
      <asp:Parameter Name="@original_CanBeDeleted" Type="Boolean" /> 
      <asp:Parameter Name="@original_TimeAdded" Type="Int64" /> 
     </DeleteParameters> 
</asp:SqlDataSource> 

我仍然得到一个错误：必须声明标量变量 “@original_MachineGroupID”

Answer 1

你不加入一个@original_MachineGroupName参数查询。您的查询引用了多个变量，并且您只添加了其中一个变量。

cmd.Parameters.AddWithValue("@original_MachineGroupID", item); 
cmd.Parameters.AddWithValue("@original_MachineGroupName", itemName); 
cmd.Parameters.AddWithValue("@original_MachineGroupDesc", itemDesc); 
cmd.Parameters.AddWithValue("@original_CanBeDeleted", true); 
cmd.Parameters.AddWithValue("@original_TimeAdded", time); 

您需要找到额外信息来满足您的查询，否则请更改您的查询以删除对它们的需求。

Answer 2

您在查询中有几个参数，即@original_MachineGroupName，但仅向您的命令对象添加一个实际参数。查询中的每个参数都需要一个。

Answer 3

下面的代码会从数据库中删除行，如果要传递到方法的字符串是在表中的主键或唯一键：

string sql = "DELETE FROM [MachineGroups] WHERE [MachineGroupID] = 
        @original_MachineGroupID"; 
    SqlCommand cmd = new SqlCommand(sql, conn); 
    cmd.Parameters.AddWithValue("@original_MachineGroupID", item); 

Answer 4

注意你的绑定也。如果从数据库中删除一行，那不会从gridview中删除数据。您将需要重新获取数据并重新绑定数据。