What is the DataField Name of a GridView bound to a String Array?

This is a special case that I don’t remember experiencing before but resolved with the help of a StackOverflow question Binding an ASP.NET GridView Control to a string array.

In a simple Asp.Net Membership management application I was simply binding a Role list to a GridView so I could click a link to see which users were members of a selected Role. I was using the following syntax in the CodeBehind where grvRoles is the GridView:

grvRoles.DataSource = Roles.GetAllRoles

grvRoles.DataBind()

Note: Roles.GetAllRoles() is in the System.Web.Security namespace which returns a string array of Roles from the aspnetdb Membership Database.

On the Designer:

<asp:GridView ID="grvRoles" runat="server" 

    EnableModelValidation="True">

    <Columns>

        <asp:CommandField ShowSelectButton="True" />

    </Columns>

</asp:GridView>

Which produced the following output with the GridView auto-generated columns. Notice the column name is “Item”, but the datasource is a string array which doesn’t technically have a DataField name like if it was bound to a Generic List or Collection of class objects.

I want to use a LinkButton where the CommandArgument is the Role name which is represented as a String value of the array. So If I convert the “Select” Command button column to a Template field, what do I use as the DataField name? Generally I would use the syntax:

<asp:GridView ID="GridView1" runat="server" 

    EnableModelValidation="True">

    <Columns>

    <asp:TemplateField ShowHeader="False">

        <ItemTemplate>

            <asp:LinkButton ID="lnkMembers" 

                runat="server" CausesValidation="False"

                CommandArgument='<%#Eval("Item") %>' 

                CommandName="Select" Text="Members"></asp:LinkButton>

        </ItemTemplate>

    </asp:TemplateField>

</Columns>

</asp:GridView>

 

Note the CommandArgument=’<%#Eval(“Item”) %>’, but that won’t work, because the String Array doesn’t actually have an Item property. Instead you can use the longhand syntax: CommandArgument='<%# container.dataitem %>'.

 

If I don’t want to have the GridView auto-generate the columns, what do I use for the asp:BoundField name? Apparently there is a secret syntax by using an exclamation point <asp:BoundField DataField="!" HeaderText="Role" />.

The breakpoint will not currently be hit. No symbols have been loaded for this document.

Doug Butscher’s blog post about the subject was able to get me debugging again in one of the Visual Studio 2010 projects in my solution. As he noted in Step 3, the Modules window indicated that the Symbols were loaded.

I stopped the debugger, deleted only the obj folder, and restarted the IDE. That was enough to fix it for me.

Vista Backup Stopped Working - Fix

I’ve been using Windows Vista’s built-in Backup and Restore functionality daily for over three years now, with good success until recently. I recently started experiencing a backup error every day for the incremental backups as well as when I attempt to create a new full backup.

The backup did not complete successfully. The file or directory is corrupted and unreadable (0x80070570)

This error message was not very helpful because it didn’t indicate which file or directory was corrupt. It also didn’t indicate whether it was my backup source Operating System partition, Files partition, or the backup destination device.

The Fix

I ran numerous utilities including the Seagate Tools (manufacturer of the source and destination hard drives) on both drives which didn’t detect any problems. The final fix was opening a Command Prompt and running “CHKDSK C: /R” where the C-drive was my primary OS disk. Because the Operating System was in use, the Check Disk utility couldn’t run until the next restart.

Backup Redundancy

The Complete PC Backup, where it creates a VHD image file of each of the backup drives, was working the entire time which provided some level of comfort while troubleshooting the traditional backup process.

photo credit: ground.zero / CC BY 2.0

Visual Studio Cloud Service for Azure Development Requires IIS7

Lately I am really wondering about the utility of using the Visual Studio built-in web server for development. Last month it was causing inconsistent rendering of AJAX modal popups, this month installing the Visual Studio Cloud Service for Windows Azure development requires IIS7.

Having the built-in web server seemed like a way to minimize the system resources and attack surface of the development workstation, but it doesn’t seem as practical anymore.

ReportViewer Woes with Tight Integration between Visual Studio and SQL Server and No Backward Compatibility

Lately I find myself creating some quick client reports (ProcessingMode=local) using the Visual Studio 2010 ReportViewer control and the Reporting Services Tablix control. The issue is that my customer is on SQL Server 2000, not 2008 as is officially supported by Visual Studio 2010 and the rdlc Reporting Build Provider. How do I know?

Mainly because of the following compile error:

“The report definition is not valid.  Details: The report definition has an invalid target namespace 'http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition' which cannot be upgraded.”   

The lack of backward compatibility was not immediately obvious, but I still wanted the ability to use the newer Tablix functionality in the VS 2010 IDE and have the out-of-the-box export functionality of the Reporting Services client reports. I’m not a fan of workarounds as I have written about before, but occasionally under special circumstances with the pros and cons heavily considered, I entertain the idea. In this case, a SQL 2008 upgrade is on the schedule in the next few months.

Workaround for Visual Studio 2010

Visual Studio 2010 cannot use any of the SQL Datasource Wizards or any other database related wizards with a pre-2005 database, which is disappointing for anyone developing “big corporate” applications as they are often late adopters. To work around this limitation in development, I backed up my SQL Server 2000 database and restored it as a SQL Server 2005 database so I could use the IDE for the Create Report wizard. Obviously, prior to deploying to production SQL 2000 servers, the database DDL and DML changes need to be scripted back out (in SQL 80 compatibility mode) and tested against SQL 2000 instances. Please don’t skip this step!

Workaround for SQL Server 2000 RDLC format

This is my least favorite part of the work around because it can be easy to forget to undue before deployment.

The application I am working with is a website project, not a web application. The compile error occurs when I try to “Build” the project from the IDE “Build” menu. If instead, I just navigate to the web page the report is hosted in (hosting in IIS, not the IDE integrated web server), the page and its report render correctly with no errors. In order to use the IDE’s build functionality, I need to “exclude” the webpage and rdlc file it is using while working on other pages of the project.

To exclude a file from the project, right click the filename from the Solution Explorer window and click “Exclude from Project”. Excluding a file in VS 2010 renames the file to [filename].[ext].exclude so you may get a Visual Source Safe or Team Foundation prompt if your files are under source control (recommended).

When I am ready to deploy or test the pages with ReportViewer controls, it is necessary to un-“exclude” the report aspx pages and .rdlc report definitions.

photo credit: Andy Welsh / CC BY 2.0

Five Reasons to Use a Staging Server

If you are interested in avoiding common and difficult to reverse issues when deploying new or updated software to a production environment, use a staging server – at a minimum. Your staging server should be configured as closely as possible to the production server. With virtualization, the process of cloning a server becomes a relatively trivial task.

A staging server provides a safe vehicle to “discover” and prevent commonly overlooked deployment issues:

1. missing assembly references or resources. This is a frequent occurrence if you use third party tools like Infragistics, Telerik, or another. When you install the development tools, they often add the assemblies to the GAC on your development box and scripts and images to “special” virtual directories. If you blindly deploy an application to production without making sure you have the assemblies either in the GAC or referenced properly in your application, it can frequently lead to run time errors and the yellow screen of death. Even items you might think are part of the .Net Framework that are pre-loaded in your Visual Studio toolbox, such as the ReportViewer control require the installation of a ReportViewer Redistributable executable.
2. dependencies on physical hardware. Depending on how the application is configured, your application may unwittingly be relying on a writeable F drive where on the server the F drive may not exist or may be a CD-ROM drive. Or require a 64 bit processor on a 32 bit server. It is better to catch these issues before deploying to production.
3. require elevated file system permissions. If your application is writing XML files or storing media, the application upload path will require Write permissions for the accessing account. Permissions requirements should be part of the installation/upgrade process, not left to post installation troubleshooting.
4. require least privileges on database permissions. You may be using the sa account (not recommended)on your development box, but your production DBA and/or company policies won’t appreciate that in production. This is an opportunity to make sure your application is running under an account or group with the least privileges necessary to run the application and make sure if your installation process is dropping/re-adding stored procedures or tables, you are also adding the appropriate grant select, insert, update, delete, execute, bulk insert, or truncate permissions to avoid unexpected SQL errors.
5. require configuration changes to interface with other services, such as IIS version differences, SMTP, or Message Queues. On your development box, for simplicity, you might be using a local IIS SMTP service, or file system implementation to test emailing functionality, but if the production environment only allows mail to relay through a Microsoft Exchange endpoint, you have some additional configuration to do. Making sure all the appropriate accounts are understood and configured properly often takes coordination with other IT specialists. They’ll appreciate it if you coordinate it at their convenience on a staging server instead of elevating the issue to a production emergency.

This isn’t intended to be an all inclusive list, but hopefully if you are not using one today, it will inspire you to consider using one in the future. Prevention is the best medicine for software implementation.

The staging process provides an opportunity to perfect the installation process for a problem free installation. Additionally, having the installation process consolidated to a single series of installation and configurations steps in a single package with all the necessary files and scripts can simplify recreating software versions for disaster recovery purposes or for replicating to additional installation deployments, such as for different customers or at a different site.

Photo credit: Anirudh Koul / CC BY 2.0

Ajax Control Toolkit Modal Popup CSS Styling issue

I found an interesting (and aggravating) difference between running a web application in the built-in Visual Studio 2010 development server vs. IIS 7 when using the Asp.Net 3.5 Ajax Control Toolkit ModalPopupExtender control. In the built-in web server (screenshot 1), the CSS formatting did not render correctly as it did in the application hosted in IIS7 (screenshot 2). Initially I used the standard styles you will find on the toolkit sample code.

Hopefully this will help some of the many other people that had the same problem.

Click the screenshots for enlarged views. The code used follows the screenshots.

ManagePeople.aspx

<asp:ModalPopupExtender ID="pnlModalNew_ModalPopupExtender" runat="server" 

    DynamicServicePath="" Enabled="True" TargetControlID="btnNew"  PopupControlID="pnlModalNew"

    BackgroundCssClass="modalBackground" DropShadow="true" 

    CancelControlID="btnCancel" >

</asp:ModalPopupExtender>

Styles.css

/* Modal Popup */

.modalBackground {

    background-color:Gray;

    filter:alpha(opacity=70);

    opacity:0.7;

}

.modalPopup {

    background-color:#ffffdd;

    border-width:3px;

    border-style:solid;

    border-color:Gray;

    padding:3px;

    width:250px;

}

The Panel pnlModalNew referenced by the ModalPopupExtender that contains the data entry form fields had the CssClass style set to .modalPopup.