Using ASPX Like MVC

I love the organization of MVC when it comes to delivering content. Using a server-side controller you can see all the routing activity of your program. The controller can interact with the parent view as well as related partials, passing data and rendering html. Related views are also tucked-away together in the tree making it easy to pinpoint what you’re looking for. The default layout of WebForms is a different kind of animal. But using MVC experience as a reference you can structure your project to work in a similar way.

To begin we want to create a Views folder and inside that create a Home directory. The Home directory will contain the parent ASPX as well as any child ASPX pages for the dynamic content. When naming the child ASPX files be sure to prefix them with an underscore to follow MVC convention:

Tree Example

Next, we need to refine the Site.Master (or _Layout.cshtml in MVC). Make sure to add the script and style bundles to get jQuery and Twitter Bootstrap on the page. The ContentPlaceHolders (or sections in MVC) allow us to have placement control:
If any bundles are missing they can be added in App_Start/BundleConfig.cs.

In this example the parent ASPX contains a button that performs an ajax request. ContentPlaceHolders are used to inject code snippets in the proper location within Site.Master:
This is pretty straightforward. The script performs an ajax request to a partial ASPX. It passes data and retrieves HTML that is displayed to the user. The Index.cs file is not touched.

Next, we want to ensure the server can locate our parent page. A simple adjustment to the Web.config can accomplish that:
Now on to Models. You can also create Models to share between parents and partials. When creating a new Web Forms templated project it comes with a Models folder already. Inside is a model for account identity. Create a HomeModel.cs and place it in that folder. Next, add the following model to it which will be referenced later:
In any ASPX file you can add a using statement to reference our models:
Replace WebForms_Ajax with the name of your project. After that, all models can be shared between ASPX pages. This can reduce redundant coding.

The last step of the process is the partial. Under /Views/Home create an ASPX page named _Incomplete.aspx. The UI looks like:
Notice we have a full HTML document here. This is necessary to use the ASP.NET Web Server Controls. If you don’t include surrounding <html> tags then it won’t recognize tags prefixed with asp. But don’t worry, when we return the markup via ajax it won’t have any of that. We simply grab the contents of the <asp:PlaceHolder> tag.

Take note of the tags. This is what we use to add data to our page. They will repeat one to many times to add content to the page. Inside that repeater is another repeater whose data source is set automatically. The Eval() calls relate to the property names of our model.

The code behind does the magic. In Page_Load we fetch the data that was passed. It can be used to retrieve any additional information from a data source. Next, we construct our model to pass to the page. The model was declared in HomeModel.cs The RootRepeater is the name of the outermost repeater. We set the class equal to it’s data source. Notice we are placing the model in a list. A repeater requires a list or other IEnumerable object to work. Lastly, we grab the contents of the placeholder and return it with the response:
Download a DEMO.

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Self-Closing Bootstrap Modal in MVC

I had a need recently to alert users if the amount of records being selected differed from what they expected. My notice was more of a "heads up" then anything. Still, I wanted to give users a way to abort situations where job size would pose a threat or hinder productivity. I also wanted to avoid extra interface clicks, especially in situations where they typically accept. That’s when I came up with the idea of a self-closing dialog. The user would be presented a modal message informing them of the difference. To proceed they could press the Continue Immediately button, close the dialog (via the title bar), or step away and wait for the timer to run out. The process only aborts if they they click the Cancel button in the allotted time.

This project could be done in a multitude of ways. Being an MVC fan I opted for that route. I decided to utilize partial views as well. Regardless of your approach you will likely need to contact the server to crunch your numbers and detect the differences. To do this you will probably use ajax:
On the backend we receive our data using a controller and models:
Next, comes the partial view. Notice I’m declaring a model and using it to retrieve values:
I also have some script in the partial to drive the modal:
And there you go.
  1. We click a button that fires ajax
  2. The ajax talks to the server
  3. The server detects differences
  4. The server populates a model then generates a partial view
  5. The partial view is returned to the ajax callback function
  6. The callback function adds it to the DOM and executes the script

Like I said this could be done in a dozen different ways. You could have the modal hidden on the parent, use ajax to fetch the figures themselves, then modify the modal before making it visible (see DEMO below). You could also use webforms to do this and use ASP.NET web server controllers instead of partial views.

See a DEMO.

Thanks.

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