Question

I have this sql query

Dim cmd As OleDbCommand = New OleDbCommand("SELECT * FROM GPS1_MAP where sta_id=" & TreeView1.SelectedNode.Value, con)

and the treeview code is here

<asp:TreeView ID="TreeView1" runat="server" AutoGenerateDataBindings="False" Font-Names="Arial"
                        Font-Size="Smaller" ForeColor="#C04000">
                        <Nodes>
                            <asp:TreeNode Text="Paties">
                                <asp:TreeNode Text="CHENAB COTTON MILLS" Value="CHENAB COTTON MILLS"></asp:TreeNode>
                                <asp:TreeNode Text="AJMER COTTON GINNERS" Value="AJMER COTTON GINNERS"></asp:TreeNode>
                            </asp:TreeNode>
                        </Nodes>
                    </asp:TreeView>

But its not working with slected value of tree what may the problem?

Answer 1

The Value of your select node (eg. <asp:TreeNode Text="CHENAB COTTON MILLS" Value="CHENAB COTTON MILLS"></asp:TreeNode>) is the string CHENAB COTTON MILLS.

Therefore your SQL statement will become:

SELECT * FROM GPS1_MAP where sta_id=CHENAB COTTON MILLS

Notice that there are no quotes around CHENAB COTTON MILLS. Your statement will therefore not be valid.

You could either add quotes around the value, such as:

Dim cmd As OleDbCommand = New OleDbCommand("SELECT * FROM GPS1_MAP where sta_id='" & TreeView1.SelectedNode.Value & "'", con)

Or use named parameters, which is a better solution (since it prevents SQL injection attacks).