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thoughts about programming
Posted by Dmytro Shteflyuk on under ASP.NET
Operator ??, that was introduced in the .NET 2.0, takes first place in my top used C# idioms list a long time, but unfortunately it is rarely used in projects I’ve participated. Therefore these snippets could be found in production code very often:
1 2 3 4 5 | public string Caption { get { return ViewState["Caption"] != null ? (string) ViewState["Caption"] : ""; } set { ViewState["Caption"] = value; } } |
Posted by Dmytro Shteflyuk on under ASP.NET
Often in ASP.NET application we see a code which looks like this one:
1 2 3 4 5 | if (Cache["SomeData"] != null) { string name = ((SomeClass) Cache["SomeData"]).Name; //..... } |
Experienced developer, even if he is not a paranoiac, will find possible problem immediately — NullReferenceException. That’s because of caching implementation in ASP.NET. In ideal case an object, that has been cached, will stay there up to application restart, but in real world it could be deleted between two calls: by the garbage collector when memory is over (because cache uses weak references WeakReference); by another thread to refresh cached data.
So the code I have mentioned before works in 99% of all cases, but sometimes you will get errors in your log, which can not be reproduced easily. Here is right cache usage approach:
1 2 3 4 5 6 | SomeClass someClass = Cache["SomeData"] as SomeClass; if (someClass != null) { string name = someClass.Name; //..... } |
Do not relax your vigilance, it’s exactly what they are waiting for! (about bugs)
Posted by Dmytro Shteflyuk on under ASP.NET
How often you are laughing out loud when looking on the someone’s code? Today I found great code in my current project and I can’t hold posting this to my blog. So,
1 2 3 4 5 6 7 8 9 10 11 | if (Request.QueryString.HasKeys()) { string[] keys = Request.QueryString.AllKeys; foreach (string k in keys) { if (k == "memberpagemode" && (string)Request.QueryString.GetValues(k).GetValue(0) == "edit") { pSett.ChangeFormViewMode(FormViewMode.Edit); } } } |
And how do you search through the hash for a key with specified value?
Posted by Dmytro Shteflyuk on under Ruby & Rails
I have a good news: Sphinx Client API has been updated and now it supports all brand new features of the unstable Sphinx 0.9.8 development snapshot. What does it mean for you as a developer? What features you will get if you would decide to switch to the new version? I will describe most valuable improvements of the Sphinx in this article, and will show how to use them with new Sphinx Client API 0.4.0 r909.
Posted by Dmytro Shteflyuk on under ASP.NET
In my current project we decided to build a Facebook application. This is really great platform with many interesting ideas inside, which usually means that you will spend a much time to make your application working as expected. Today I wanna talk about user profiles. Any Facebook application could add some action links, which will be displayed under the user’s picture, and some content for wide or narrow column. Of course, you can use FBML syntax, especially fb:if-... tags set to choose which content to show on specific profiles to concrete users.