Skip to main content

Working with autocompletes in NRapid

Image
By

One of the main goals behind relational databases design is reduce/eliminate the amount of duplicated data. In order to do that, they split the data into multiple tables and relate them by FK. While this works really well in database terms, they don’t when it comes to searching or loading data (In highly normalized database we usually need a lot of JOINs)
Continuing with an example that we were working on previous posts (products by category) we can see this design lines in action.


The goal of our report is allow the users to select a category, and based on that category, fetch the corresponding list of products. The problem is, if we look at the products table, the product's category is and ID (numeric), which is hard to remember and does not make any sense on his own. In this kind of scenarios, we can use the autocomplete control. This control will allows to the user to filter by description (category name) or any field that make sense to him/her and pass to the report engine the corresponding ID to filter the relational data (in this case, the category ID).
To get an autocomplete in our dialog, we need to define a class that looks something like this:
* Annotations are required because we are working with a "legacy database” wich does not follow the NRapid conventions, more on this in future posts.
As you may already guess, CategoryName is the field that we are going to use to provide some sort of searching feature, and CategoryID is the field we will use to query the database.
Ones this class is done, we only need to add a property to the nested class “Dialog” (seen in previous posts) and NRapid will take cares of the rest.

The code to configure the report should look something like this (note that in the view data we are getting the Category ID)



When executing the report, you will see a textbox labeled “category”, pressing F2 will a show a list of categories, select one and confirm the dialog.


On the next post, customizing autocompletes. Stay tuned!

You can get the source code of NRapid from here
And the sample app from here
The Northwind database is available from download at http://www.microsoft.com/en-us/download/details.aspx?id=23654

Labels:

Comments

Post a Comment

Popular posts from this blog

Migrating an ASP.NET MVC 4 app from Azure websites to WinHost

By
About a week ago I've to migrate an ASP.NET MVC 4/EF5 application from Azure websites to WinHost. While the process was really smooth, there were some caveats related to database connections that I want to share with you. Create and setup the ftp profile on VS and configure the connection string was really easy, WinHost provide you those values and there is nothing special here. But once you deploy your website and try to see it online, you may get the “yellow screen of dead” with the message: "A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)" Assuming you wrote the connection string properly, this happens because you cannot use the default connection name in your web.c
2 comments
Read more

How to show excel files inside the .NET Webbrowser Control

By
If you are reading this, chances are you been banging your head against the wall for a couple of hours (or even days) trying to show excel files inside the WinForms webbrowser control. Possible reasons you ended up in here: You had working code that got broke after upgrading from Win 7. Your code doesn’t work the same way between machines running different (newer) versions of IE. A download box pops up every time your app tries to show an excel file inside the webbrowser control (you wanna show the actual content). You just have no clue on how to get excel working into the .NET embedded webbrowser control. You are trying to implement IInternetSecurityManager and don’t know where to start. (Or how don’t know how to delegate calls to your security manager). Among many other, maybe….. Yes, COM is a PITA, so is ActiveX and IE (Embedded or full for that matter). And no, showing excel files inside the webbrowser control shouldn’t be that hard, but sometimes we have
3 comments
Read more

How to replace text with images on Word documents using C#

By
This post it’s a reply to a question I got from a previous post that shows how to work with Word templates from C# code . If you haven’t read it, I recommend to do so because I’m not going into details here. But basically it was about how to create a Word document from a template and perform same text manipulation. So, the question from Marcel Kieboom  was “Do you know if it would be also possible to replace one of the words with an image which is locally stored?” The answer is yes, and this is how you can do that. Based on the same convention I had used in the previous post, I should have a template like this: What I’m trying to do here is replace the text [angus-young] for an actual pic of Angus. The technique I’m using it’s pretty common on web sites and basically consist in have an image with a matching name for each keyword I want to replace and then create the image path dynamically. This is the C# code to do that. * When I execute the f
19 comments
Read more