forum.codecall.net Tutorials

RGB to hex colors and hex colors to RGB
When using Colors in HTML and CSS you need to use a hexadecimal color (something like #FFFFFF) which is the base 16 value from the RGB color scale. Sometimes you'll need to use the RGB scale instead, for example when allocating colors when drawing images with PHP and you maybe just prefer to write it in one of the ways even though you need to have it in the other. I will in this tutorial show you how you can make two functions(fromRGB and toRGB) which can convert hexadecimal colors to RGB colors and vice versa.

Graphics Tutorial
I will in this tutorial show you how to create images with PHP, this uses inbuilt functions and doesn't need anything else then just PHP to work.

The Ternary operator
The Ternary comparison operator is an alternative to the if-else statement, it's shorter and could be used to easily do a significant difference depending on a condition without the need of a if statement. The Ternary operator is made for two different actions, one if the condition is true, the other one if it's false but with nested Ternary operators we can use it like an if-elseif.else statement(more to that later).

How to use Cookies
Cookies is small text files saved locally on the user's computer by the website, when the website later on wants the information it just reads the cookie on the user's computer. An example on what you can use cookies for is to see if the user has visited the site before, if it has then a cookie you saved the last time lies on the computer so therefor you can only check if it does.

Simple file uploader
I'm going to explain you how you can make a simple file uploader.

Debugging MySQL issues
Possibly the most common issue users have with PHP is working with MySQL. Executing a query requires a three step process: 1. Connecting to your database server. 2. Selecting a database. 3. Executing the query. When a query fails, many users don't know where to begin debugging. This guide outlines my debugging procedure.

Very Simple C Calculator
This tutorial is for newbie C programmers. It uses basic skills and makes a useful program. Things you should know: #How to use scanf and printf #How to use if and while #How to declare variables know about variable types

Turning the printf statements on and off
When it comes coding a program, we normally use printf statements to test or debug the code. When the coding gets completed, we find these printf statements are no longer needed, so we remove them.

Double buffering, movement, and collision detection
Those looking to get into game programming with java will likely find this tutorial more interesting than others. This tutorial will cover: Collision detection, movement via keyboard, double buffered animation, and a basic game loop. We are basically going to create a window with swing, actively render two double-buffered rectangles, move them around the screen, and check for collisions between them, all while using a basic game loop. I am going to be as Object Oriented (OO) as I can, so we will be creating a few classes.

Multidimensional Arrays
This is a tutorial about multi-dimensional arrays, however a quick review of 1-dimensional arrays. The understanding of a 1-dimensional array is crucial to understanding 2 and 3-dimensional arrays.

Generics and the Stack
Using generics allows you to define classes that can work with any defined type. This is very similar to the use of templates in C++. When you use collections like the vector and the stack you do not have to do any typecasting to get the correct value. This ensures that you cannot make silly errors with getting items from a collection. Without generics we had to use typecasting to get the correct data out of structures. The other problem is we are going to have problems if try to add the wrong data type. Generics ensure that we use the right data type and that we do not have any typecasting to do.

jQuery: Selectors
In this tutorial I will be teaching you all the selectors of jQuery. jQuery is a very powerful AJAX/Javascript based framework, that can be downloaded freely (link at the bottom of the tutorial). If you wish to use jQuery, you don't need to have any knowledge of Javascript at all.

innerHTML
InnerHTML allows you to change parts of a web page dynamically. In my last tutorial about GET and POST in PHP, I showed how you could use a button and a textbox and then use GET or POST to print that text on the page. However, to do this, it refreshed the page. Using innerHTML, we will do it without refreshing the page. And, in another tutorial, Ill be showing how to use ajax and innerHTML to be able to do things like pull information from a database and then use innerHTML to show it. But, on with this tutorial .

Ajax with Mootools
This tutorial will be about using the Mootools JS library with ajax, if you dont know a thing about ajax you will do just fine with mootools. but you need to have know some javascript to keep up.

Dates - Get Methods
The JavaScript language contains a very useful Date object for manipulating dates. With this object you can do all sorts of really fun and interesting things.

Tutorial: Showing images stored in MySQL
Show images stored in a BLOB in MySQL

Creation of captcha / Part II /Secure forms
Creation of a captcha image using secure forms.

Starting C# with C# 2008 Express Edition
Starting with C# using Visual C# 2008 Express Edition

Tutorial: Advanced SQL
SQL is perhaps, a very easy language, so here we will try to explore its advanced nature...so that you will see that you can do a lot more with SQL. More than just "select", "order by" and so on...

Getting to know GD
Getting to know GD by using this tutorial.