Archive for the ‘.NET 4.5’ Category
Posted by jpluimers on 2014/01/30
A while ago, I was refactoring some C# 1 code that uses HashTables as a poor mans property bag.
The problem was that I felt my code was convoluted, and should be denser, especially avoiding Convert.ChangeType. My code was already much simpler than casting tuples to a superclass.
So I asked this question on StackOverflow: c# – Is there a solution that feels less clumsy than Convert.ChangeType to get the value from a HashTable – Stack Overflow.
User dasblinkenlight showed it could be shortened and explained why (hyperlinks are mine):
Since System.String is sealed, the expression
genericType.IsSubclassOf(stringType)
is the same as
genericType == stringType
Therefore you do not need a call of Convert.ChangeType: you can cast to T by casting to object, like this:
object stringResult; // Note the change of type to "object"
if (haveValue)
stringResult = ((string)properties[propertyName]).Trim();
else
stringResult = string.Empty;
result = (T)stringResult; // It is allowed to cast object to generic T
The original .NET 1.1 code had loads of null checks wrapped if/then/else statements to assign default values for null values.
I wanted to get rid of that, and get code like this: Read the rest of this entry »
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/01/29
In the .NET/C#: fun with enums and aliases part 1 you saw that an enumerated type can specify an underlying type.
The underlying type is limited to a strict set of built-in C# types: , so you cannot use a CTS type for it.
So you might think that you can only define enumeration values by integer constant like this:
namespace BeSharp
{
enum TwoState
{
False = 0,
True = 1,
}
enum ThreeState
{
False = 0,
True = 1,
Unknown = -1,
}
}
Well, you can do it like this too, since Operations between different enum types are allowed in another enum declaration: Read the rest of this entry »
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/01/21
I remember doing this in DOS ages ago (in the Turbo Pascal 5 era) for exactly the same reason: flash the keyboard LEDs to indicate some event was happening, but I’ve yet to find back the source code.
Here is how to do it in Windows using either C# or C: Faking num lock, caps lock and scroll lock leds – About My Code.
–jeroen
via: c# – Way to turn on keyboard’s caps-lock light without actually turning on caps-lock? – Stack Overflow.
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, C++, Development, Pascal, Software Development, Turbo Pascal | Leave a Comment »
Posted by jpluimers on 2014/01/15
At clients, I see quite a few people being confused by this compiler error message:
Error 1 The type 'string' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or method 'System.Nullable'
One of the reasons about the confusion is that a string variable behaves like a value type, but in fact is a reference type because their values can consume a huge amount of memory (thanks User codekaizen).
A few interesting questions on that on StackOverflow:
Anyway, back to the error message above.
Lots of people are confused by it, just see a few questions on StackOverflow: Read the rest of this entry »
Posted in .NET, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, Jon Skeet, Software Development | Leave a Comment »
Posted by jpluimers on 2014/01/09
Reading c# – Type.IsSubclassOf does not behave as expected – Stack Overflow, I found this very interesting link via Assembly Load Contexts Subtleties at Sasha Goldshtein’s blog (I love the name of the blog: All Your Base Are Belong To Us).
He explains the reasons for the error message
System.InvalidCastException: Unable to cast object of type ‘Plugin.MyPlugin’ to type ‘Plugin.MyPlugin’.
Actually his blog entry is an abstract of a 200+ page thesis on that is also recommended reading: Flexible Dynamic Linkin for .NET (by Anders Aaltonen, Alex Buckley and Susan Eisenbach).
–jeroen
via:
Posted in .NET, .NET 3.5, .NET 4.0, .NET 4.5, .NET CF, C#, C# 3.0, C# 4.0, C# 5.0, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/01/07
Thanks Pedro! (emphasis below is mine)
The ContextSwitchDeadlock doesn’t necessarily mean your code has an issue, just that there is a potential.
If you go to Debug > Exceptions in the menu and expand the “Managed Debugging Assistants”, you will find ContextSwitchDeadlock is enabled.
If you disable this, VS will no longer warn you when items are taking a long time to process.
In some cases you may validly have a long-running operation.
It’s also helpful if you are debugging and have stopped on a line while this is processing – you don’t want it to complain before you’ve had a chance to dig into an issue.
–jeroen
via: c# – Visual Studio: ContextSwitchDeadlock – Stack Overflow.
Posted in .NET, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, Development, Software Development, Visual Studio 11, Visual Studio 2005, Visual Studio 2008, Visual Studio 2010, Visual Studio and tools | Leave a Comment »
Posted by jpluimers on 2014/01/01
For a project, I needed to strip the potential Path.DirectorySeparatorChar and Path.AltDirectorySeparatorChar.
Where Path.Combine will combine two paths and insert the DirectorySeparatorChar, I could not find the opposite, so I wrote this little piece of code:
using System.IO;
namespace BeSharp.IO
{
public class PathHelper
{
public static string RemoveTrailingDirectorySeparators(string directory)
{
string result = directory.TrimEnd(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar);
return result;
}
}
}
–jeroen
via:
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2013/12/26
My mental association with getting LogicalDrives was always the System.IO namespace, so I’ve always used Directory.GetLogicalDrives Method (System.IO) .
Recently I bumped into Environment.GetLogicalDrives Method (System), and discovered it has been available for the same time: since .NET 1.x.
I was not so much amazed that these methods return exactly the same data, but that they have identical code. Not just a single call to some common code: their code is the same, line by line. In .NET 4, they have the code below. Read the rest of this entry »
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2013/12/25
StackOverflow user Joe (sorry, no last name) helped me big time by answering my question on Business logic shared by ASP.NET / WinForms: find the location of the assembly to access relative files to it.
Before showing the code at the bottom of this blog post, let me explain the question in more detail:
Basically I was in the midst of refactoring some ‘inherited’ business logic code that – before refactoring – for the ASP.NET side needs to be initialized with an absolute path, but on the WinForms / WPF side only with a relative path to a GetExecutingAssembly directory.
To ease xcopy deployment, I wanted all configuration settings to be relative. But I hadn’t found a common means for these platforms to obtain a directory usable as a root for accessing relative files.
That way I could put identical settings in both the Web.config and App.config, heck even generate them based on a common fragment, whithout having to hard-code absolute path names.
I knew about Assembly.GetExecutingAssembly, but in ASP.NET that location is not where the web site is (both IIS and the WebDevelopment server make use of temporary locations to store the assemblies).
ASP.NET does have Server.MapPath and HostingEnvironment.MapPath, but I didn’t want to make the business logic depend on ASP.NET.
Joe came up with this solution, which works dandy: Read the rest of this entry »
Posted in .NET, .NET 1.x, .NET 2.0, .NET 3.0, .NET 3.5, .NET 4.0, .NET 4.5, ASP.NET, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, F#, Prism, Software Development, VB.NET, VB.NET 10.0, VB.NET 11.0, VB.NET 7.0, VB.NET 7.1, VB.NET 8.0, VB.NET 9.0, Web Development | Leave a Comment »
Posted by jpluimers on 2013/12/22
Cool stuff: DelphiSpec library, inspired by Cucumber. It runs on top of DUnit.
via DelphiSpec Library Announce « Роман.Янковский.me.
A similar one in the .NET realm: SpecFlow – Pragmatic BDD for .NET.
–jeroen
Posted in .NET, .NET 3.5, .NET 4.0, .NET 4.5, C#, C# 3.0, C# 4.0, C# 5.0, Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Development, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 