Back End 

The back end Administration will have a Master page for navigating the News items with Add, Edit, and Delete features as well as an Update Settings page where the back end access password/username can be changed. We have a lot to do so let’s get started.

The Master Page

Create a new ASP.NET VB page and save it as “/admin/admin_news.aspx.” This will be our master page. Define a dataset selecting all from the “tbl_New” table. Insert a table, three columns, three rows. In the top and bottom rows enter the text “Add News Item.” Make each instance a hyperlink pointing to “add_news.aspx.” Drag the headline into the first column of the middle row. Move to the second column. Type “Edit” and make it a link that points to” /admin/edit_news.aspx?N_ID=” then drag the dataset N_ID field onto the page and insert it in the query string as we did before. In the final column type “Delete” make a link to “/admin/delete_news.aspx?N_ID=” again using the N_ID dataset field value as our query string parameter. That’s it. The coding is done here.

The Delete Page

Open a new page and save it as “/admin/delete_news.aspx?N_ID=.” Select “Delete Record” from the Server Behaviors drop down. You'll see the “delete record” dialog. Select “Primary Key Value” from the first drop down. Select your connection “datasource.” Select the table “tbl_New.” From the “Primary Key Value” drop down, select “URL Parameter” and enter “N_ID” in the text box. Finally click the “Browse” button and select “/admin/admin_news.aspx” for redirect on success. Save the page and close it because you’re done. When you click the “Delete” link from the admin page the delete will happen so fast you won’t see it, so be careful.

The Edit & Add News Item Pages

The add news page will be our first exposure to server controls. Server controls are ASP.NET objects of various complexity and size. The first server controls we’ll be using are the ASP.NET version of form fields, asp:textbox. Fortunately these server controls will be inserted automatically when you select “Insert > Application Objects >Record Insertion Form.” This will bring up the “Record Insertion Form” dialog. (If you look you’ll see a sister command for “Record Update Form.”) Highlight the “N_ID” line and delete it from the update. Click OK. This returns you the design environment. Delete the row in the form with the date field and insert a hidden field anywhere between the form tags. Name it “N_Date.” This will hold the date posted. In Classic ASP we could simply write <%=Date()=%> in the hidden input value field.  In ASP.NET, however, this will not work. In ASP.Net we use the DateTime.Today Property. Your hidden input should look this:

<input name="N_Date" type="hidden" id="N_Date" value="<%=DateTime.Today %>">

Now that we have our form we need form field validation. Don’t even bother trying to apply “Validate Form” from the “Behaviors” menu. No, we’re going to have to get our hands dirty and hand code the form field validation. At least the info on the Microsoft Quick Start was quite good. I found lots of helpful and easy to understand information here—including form field validation: http://asp.net/Tutorials/quickstart.aspx. We’ll be using ASP.NET client side form validation. We’ll need two functions for this, one in VB.NET, the other in Java Script.

VB.NET:

<script language="VB" runat="server">
Sub Page_Load
  If Not IsPostBack
  'Validate intially to force *s to appear before the first round-trip
  Validate()
  End If
End Sub
</script>

Java Script:

<script language=javascript>
<!--
    function ClientOnChange() {
       if (typeof(Page_Validators) == "undefined")
          return;
       document.all["lblOutput"].innerText = Page_IsValid ? "Page is Valid!" : "Some of the required fields are empty";    }
// -->
</script>

      In ASP.NET we use the RequiredFieldValidator control to perform simple field validation. The syntax of the RequiredFieldValidator is simple:

<asp:RequiredFieldValidator id="RequiredFieldValidator1" runat="server" ControlToValidate="N_headline" ErrorMessage="*" Display="Static"> </asp:RequiredFieldValidator>

The first thing we need to do to our “Add News Item” page is add the asp:label control referenced by the vb script sub routine that fires on the page load event. It should look like so:

<asp:Label ID="lblOutput" Name="lblOutput" Text="Fill in the required fields below" cssclass="errortxt" runat=server />

Now add the required field validation controls for the N_headline and N_Paragraph asp:textbox controls. The required fields reference the asp:textbox controls with the ControlToValidate property.  We also need to modify the N_headline and N_Paragraph asp:textbox controls for the dynamic client side validation by setting the onchange event property to ClientOnChange. The result will look something like this.

<asp:RequiredFieldValidator id="RequiredFieldValidator1" runat="server" ControlToValidate="N_headline" ErrorMessage="*" Display="Static"> </asp:RequiredFieldValidator>

<asp:textbox Columns="25" ID="N_headline" MaxLength="150" Rows="1" runat="server" TextMode="SingleLine" onchange="ClientOnChange();" />

Assuming you’ve added the RequiredFieldValidator to the N_headline and N_paragraph asp:textbox, you can save and close.  

The “Update News Item” and “Update Settings” forms are built following the same procedure outlined above for the “Add News Item” page—with the exception that you insert a “Record Update Form” instead of an “Insert Record Form” but that should be obvious. The other difference is the Update SB requires a hidden input on the page to hold the TableName_ID value. When using then “Insert > Record Update Form” the TableName_ID value is added to the form as asp:label text. You should change this to a hidden input as this autonumber field cannot be changed.

<input name="Admin_ID" type="hidden" id="Admin_ID" value="<%# ds_user.FieldValue("Admin_ID", Container) %>">