Quick introduction to Pex

Pex and Moles is new testing and code analysis technology that is created by Microsoft Research. Pex is powerful tool that helps you analyze your code, detect error situations and generate parameterized unit tests. In this posting I will give you quick and illustrated overview of Pex.

How to dump object properties

I needed a quick’n’dirty way to inspect objects returned from external source. I wrote simple object properties dumping mechanism you can use to investigate unknown objects. It is really quick and really dirty.

Using MemBus for messaging between application components

Sometimes we need publisher/subscriber messaging in our applications to broadcast messages to different parts of system in real time. We can always build our own solution for this but we can also use something that is already there. In this posting I will show you how to use MemBus to send messages from MDI parent […]

Using timer based Unit of Work and Command classes to measure repositories performance

In my last post Find out how long your method runs I introduced how to measure the speed of code using actions. In this posting I will make a step further and give you some ideas about how to create easily measurable code units and how to build measurable scenarios of them. As a foundation I use simplified versions of patterns like Command and Unit of Work.

Find out for how long your method runs

I am making some experiments with large database and different O/R-mappers. To make it easier for me to measure the time that code takes to run I wrote simple command class that uses Stopwatch class and measures how long it takes for action to run. I this posting I will show you my class and explain how to use it.

Experiment: List internals and performance when adding new elements

Lists and their performance has been hot discussion topic for years. I have seen many examples and read a lot of stories about List class and I made conclusion that there is too much pointless opinions about it. In this posting I will show you how List performs when adding elements to it and how it works internally. Be prepared for interesting discussion!

Managing business object locks on application level

Today I worked out simple application side object locking solution for one server scenario. My motivation came from ASP.NET architecture forum thread How to solve concurrent site issue where one user asks for locking solution that works without changing database. Here is my simple and primitive solution that should help this guy out. I added also sample solution to this posting.

Using ExcelPackage to create Excel sheets on server

In one of my community projects I needed to output some listings as Excel file. As installing Excel to server is non-sense that I was easily able to avoid I found simple solution for Excel 2007 files – open-source project called ExcelPackage. In this posting I will show you hot to create simple event attendees report in Excel 2007 format using ExcelPackage.

JavaScript: Creating timestamps with time zone offsets

I was converting the example code of my Windows Azure session to Visual Studio 2010 solution called MVC Time Planner when I discovered some date and time offset issues in my JavaScript code. In this posting I will show you some useful tricks you can use to convert JavaScript dates and times to timestamps.

Code Contracts: validating arrays and collections

Validating collections before using them is very common task when we use built-in generic types for our collections. In this posting I will show you how to validate collections using code contracts. It is cool how much awful looking code you can avoid using code contracts.

Code Contracts: How they look after compiling?

When you are using new tools that make also something at code level then it is good idea to check out what additions are made to code during compilation. Code contracts have simple syntax when we are writing code at Visual Studio but what happens after compilation? Are our methods same as they look in code or are they different after compilation? In this posting I will show you how code contracts look after compiling.

Enabling XML-documentation for code contracts

One nice feature that code contracts offer is updating of code documentation. If you are using source code documenting features of Visual Studio then code contracts may automate some tasks you otherwise have to implement manually. In this posting I will show you some XML documentation files with documented contracts. I will also explain how this feature works.

Code contracts and inheritance

In my last posting about code contracts I introduced you how to force code contracts to classes through interfaces. In this posting I will go step further and I will show you how code contracts work in the case of inherited classes.

Invariant code contracts – using class-wide contracts

It is possible to define invariant code contracts for classes. Invariant contracts should always hold true whatever member of class is called. In this posting I will show you how to use invariant code contracts so you understand how they work and how they should be tested.

Forcing code contracts through interface contracts

Sometimes we need a way to make different implementations of same interface follow same rules. One option is to duplicate contracts to all implementation but this is not good option because we have duplicated code then. The other option is to force contracts to all implementations at interface level. In this posting I will show you how to do it using interface contracts and contracts class.

Code Contracts: Unit testing contracted code

Code contracts and unit tests are not replacements for each other. They both have different purpose and different nature. It does not matter if you are using code contracts or not – you still have to write tests for your code. In this posting I will show you how to unit test code with contracts.

Windows Phone 7 development: Using isolated storage

In my previous posting about Windows Phone 7 development I showed how to use WebBrowser control in Windows Phone 7. In this posting I make some other improvements to my blog reader application and I will show you how to use isolated storage to store information in phone.

Previous Posts Next posts