Categories: Programming

How to use alias for using-directives and namespaces in C#

Posted by Raffael on Posted in C#.Net Tagged , , , , ,

Anyone who has already written one or the other program in Visual Studio with C# probably knows the following problem. Sometimes you use different libraries (Dlls) from different developers/vendors. Partly also libraries that fulfill similar purposes. This might go well, but it doesn’t have to.
Often you will get confronted with an error message like this: “‘XYZ’ is an ambiguous reference between ‘LibraryA.XYZ’ and ‘LibraryB.XYZ’”
What next? In the following I’ll explain how to solve this kind of error by taking the example of the AForge library. For instance we profess that we included the following using-directives into our program.
using System.Drawing;
using AForge.Imaging;
So now, if we use the class “Image” in our program, we will see the following error message, which result from the fact that there are two “Image” classes referenced. One in the System.Drawing namespace as also one in the AForge.Drawing namespace. Visual Studio (and later on it’s compiler) doesn’t know which Image class to […]

Benchmark: strtotime() vs DateTime vs getTimestamp in PHP

Posted by Raffael on Posted in PHP Tagged , , , , , , , ,

Recently I wrote about how one can implement date comparison in PHP. In the article I presented two approaches. Firstly, using the strtotime() method and another with the DateTime class.
Then, in the comments on the german division of this blog, it was pointed out that the strtotime() variant is probably faster. Because I wasn’t sure about this, I decided to make a small performance test and share the results with you in this article.
How did I test the performance?

Since the question aims on strtotime() vs. DateTime, the DateTime class is contrary to the strtotime() function. So because DateTime class offers more functionality, I had first to create the DateTime object and then get the timestamp of it, because the strtotime function gives a timestamp as return value and I wanted to compare the time needed to generate the identical output.
As input I have taken a date without a custom time […]

How to compare dates in PHP

Posted by Raffael on Posted in PHP, Test Tagged , , , , , ,

php_date_compareHow to actually compare 2 dates in PHP with each other? The question sounds easier than it is.  The first thought that usually comes is the following. We store both dates as strings and compare them.
Preliminary

<?php
$date1 = "2012-1-12";
$date2 = "2011-10-12";

if ($date1 > $date2)
echo "$date1 is newer than $date2";
else
echo "$date1 is older than $date2";
?>

Output:

2012-1-12 is newer than 2011-10-12

At first glance this seems to be a workable solution. But what if the two data is in a different format?

<?php
$date1 = "12-1-12";
$date2 = "2011-10-12";

if ($date1 > $date2)
echo "$date1 is newer than $date2";
else
echo "$date1 is older than $date2";
?>

Output:

12-1-12 is older than 2011-10-12

Now the date in 2012 is declared to be older than the date in 2011, which is of course wrong. However, from PHP’s point of view, this behavior is correct, because two strings were […]

How to execute Perl scripts in Notepad++

Posted by Raffael on Posted in Perl, Tutorials Tagged , , ,

notepad++_perl_executeA few days ago I already described how to set up the Eclipse development environment for usage with Perl scripts. If you don’t want to use a sledgehammer to crack a nut,  you can also use the Notepad++ editor to relatively comfortably write Perl scripts.
Besides syntax highlighting and intellisense aka auto completion, Notepad++ also offers the possibility to execute Perl scripts directly from the editors interface. However, therefore a one-time setup is necessary, which I want you to briefly explain below.
Step 1 – create test scripts:
perl-skripte_in_npp_ausführen_1  perl-skripte_in_npp_ausführen_2
To be able to check if you have set up everything correctly later, you should definitely first create a small Perl script and save it. Important: Only stored scripts can be executed afterwards. So always […]