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Showing posts from April, 2014

Make simple music program with beep(freq, duration) with Pascal

Pascal is my first programing language when I have studied in high school. It was really exciting for me. :)

The Pascal programming language was created by Niklaus Wirth in 1970. It was named after Blaise Pascal, a famous French Mathematician. It was made as a language to teach programming and to be reliable and efficient. Pascal has since become more than just an academic language and is now used commercially.

I tried to make a simple music program by using Lazarus IDE on MS Window 7, 64-bit. It frustrated me a few times how difficulty to use Sound command to make a sound. Sound did not work on my compiler and my platform anymore. So far, I just could use beep(freq, duration) from window unit to implement my work.

Here is my code. ;)
program mysong; uses Windows, crt; const C: Integer = 512; { x = A * EXP(LN(2)/12)} C_: Integer = 542; D: Integer = 574; D_: Integer = 608; E: Integer = 644; F: Integer = 682; F_: Integer = 723; G: Integer = 766; G_: Integer = 8…

Only allow input number value with autoNumeric.js

autoNumeric is a jQuery plugin that automatically formats currency and numbers as you type on form inputs. I used autoNumeric 1.9.21 for demo code.

1. Dowload autoNumeric.js file from
2. Import to project
<script src=""></script> <script type="text/javascript" src="js/autoNumeric.js"></script> 3. Define a function to use it
<script type="text/javascript"> /* only number is accepted */ function txtNumberOnly_Mask() { var inputOrgNumber = $("#numberTxt"); inputOrgNumber.each(function() { $(this).autoNumeric({ aSep : '', aDec: '.', vMin : '0.00' }); }); } </script>
4. Call the function by event
<form> <input type="text" value="" id="numberTxt"/>(only number) </form> <script type="te…

Managing JAR files with Apache Maven

Apache Maven (Maven) is a software project management and comprehension tool. Based on the concept of a project object model (POM), Maven can manage a project's build, reporting and documentation from a central piece of information. Why Maven? Let’s learn about the Maven’s history here to understand why Maven is created.
There are a lot of useful things that we should use Maven. In my opinion, the most important thing is that Maven solves the problems with managing jar files. It centralizes these files in one place and it is easy to use by declaring dependencies in a xml file (pom.xml).  Using Maven to manage JAR files Firstly, I would like to give you an example about using some JAR files without Maven.  In my project, I need some JAR files such as SNMP4J.jar, jta26.jar, jgraphx.jar, etc… so I had to search them on the Internet with visiting a lot of websites, download and add these files into my project.
My example proje…