Use your personal blog with Windows Live Writer
I’m very glad to tell you that your ".NET Research" personal blog is compatible with Windows Live Writer. You can compose, format, insert photos inside your posts offline and publish when you become online totally from this client without even opening the ".NET Research" site. Let us the steps to do this assuming you have properly installed Windows Live Writer.
Step 1. Run Windows Live Writer and Weblog > Add Weblog account..
Step 2. Choose another weblog service like the following screen and click Next:
Step 3. Now type http://dotnetbd.org as your Weblog Homepage URL, enter your credential like here I used as admin:
Now Windows Live Writer will download some necessary files to work offline and will appear with a white blank screen for you to write your first post! That’s it. These simple two steps will enable you to use this powerful tool to work with your ".NET Research" personal blog. Happy blogging!
LINQ to Flickr
One of my colleagues Mehfuz Hossain developed a wonderful open source project which allows you to query Flickr photos by LINQ, also lets you insert, delete photos directly to/from Flickr. You wonder how to extend LINQ in such an amazing way? It’s easy by writing your own custom LINQ provider, which was not-so-easy until he came up with another handy open source project named LINQ Extender. He did all the expression parsing stuff to ease our pain. Now you can make your own LINQ to Anything using this so easily.
For your heads up on LINQ extenders, here he wrote an article and LINQ to Flickr, open source project is hosted at Codeplex.
A "transactional" generic DbHelper for LINQ to SQL
In LINQ to SQL, the data model of a relational database is mapped to an object model expressed in the programming language of the developer. When the application runs, LINQ to SQL translates into SQL the language-integrated queries in the object model and sends them to the database for execution. When the database returns the results, LINQ to SQL translates them back to objects that you can work with in your own programming language. You may want to make a data access layer that separates the data operation from business layer like the following:
DbHelper.Insert<Student>(
new Student()
{
FirstName = “Tanzim”,
LastName = “Saqib”,
Email = “me@TanzimSaqib.com”,
Website = “http://www.TanzimSaqib.com”
}, true); // Use Transaction?
To make use of such transactional generic DbHelper, you might want to write a singeton DbHelper class like the following. You might notice that the class is singleton, it’s static and the DataContext is being used is private, and only initialized using the connection string if not yet.
public static class DbHelper { private const string CONNECTION_CONFIG_NAME = “StudentServerConnectionString”; private static StudentServerDataContext _StudentServerDataContext = null; public static StudentServerDataContext GetDataContext() { if(_StudentServerDataContext == null) _StudentServerDataContext = new StudentServerDataContext (ConfigurationManager.ConnectionStrings [CONNECTION_CONFIG_NAME].ConnectionString); return _StudentServerDataContext; } public static void CleanUp() { _StudentServerDataContext.Dispose(); _StudentServerDataContext = null; } // … code edited to save space
On application wide error or on end you can dispose the context so CleanUp method is useful here. To implement an Insert method see the following. You will find I have used a TransactionScope which ensures that the transaction is taking place without any interruption. If there is really any error the scope.Complete() method never gets invoked. This is how it ensures that the code inside the TransactionScope is taking place as a transaction. It is available from .NET 2.0 framework.
public static void Insert<T>(T t, bool isTransactional) where T : class { if (isTransactional) { using (var scope = new TransactionScope()) { Insert<T>(t); // On any Exception, Complete() method won’t be invoked. // So, the transaction will be automatically rollbacked. scope.Complete(); } } else Insert<T>(t); } public static void Insert<T>(T t) where T : class { using (var db = GetDataContext()) { db.GetTable<T>().InsertOnSubmit(t); try { db.SubmitChanges(); } catch (Exception e) { // TODO: log Exception throw e; } } }
I did not show other methods as part of the CRUD implementation. The rest is left open for you to implement.
[New Article] 7 ways to do Performance Optimization of an ASP.NET 3.5 Web 2.0 portal
Web 2.0 applications are widely developed. These applications often work with third party contents, aggregate them, make various use of them and then make something useful and meaningful to the users. For the past few years, developers were also engaged with such endeavors and a lot of their websites have not addressed performance issues, thus resulting in an unpleasant experience to the users.
Performance is a vast area and great results can never be achieved by a silver bullet. This article explores some of the key performance issues that can occur while developing a Web 2.0 portal using server side multithreading and caching. It also demonstrates model driven application development using Windows Workflow Foundation.
HttpRequestFactory vs. XMLHttpRequest in Volta
HttpRequestFactory was designed for use by tiersplitting internally and was not supposed to be exposed as part of the Volta API as Danny van Velzen from Microsoft Volta team told me today. So, its better if you use XMLHttpRequest instead because this factory class might not show up in the later releases. You will find this class in Microsoft.LiveLabs.Volta.Xml namespace. As like as JavaScript’s one, in this .NET version you can also Open URL, specify method name, and of course pass credentials. You can track response text, xml, status code, status text and also you can abort.
To retrieve your content, you must subscribe to ReadyStateChange event with a HtmlEventHandler which you can find in Microsoft.LiveLabs.Volta.Html namespace and check the status code. If it is 200 that means "HTTP OK", you can take the ResponseText or ResponseXML. See this example:
string content = string.Empty; var request = new XMLHttpRequest(); request.ReadyStateChange += delegate() { if (request.Status == 200) content = request1.ResponseText; }; request.Open("POST", "http://tanzimsaqib.com/feed/", true);
However, you cannot fetch cross domain content by XMLHttpRequest. The Volta compiler creates client side JavaScript XMLHttpRequest and lets developers write code in .NET friendly way. So, I do not think there is any way to retrieve cross domain content in Volta, and leaving us on the same old HttpRequest class.
