It replaces the spaces with a hypen (-), good for SEO and clean url string.
Example: “Room nr IT Park and Country Mall”
Becomes: “Room-nr-IT-Park-and-Country Mall”

function hypenate($url){
        $patterns[0]= "/,/";
        $replacements[0]="";
        $patterns[1]="/\s\s+/";
        $replacements[1]="-";
        $url = preg_replace($patterns,$replacements,$url);
        return $url;
}

Usage in PHP

hypenate("The quick brown fox");

output: The-quick-brown-fox

It can also remove out specific string you don’t want to show up on your url e.g. a comma “,” just specify it on the patterns[0] array in regular expression form

 $patterns[0]= "/,/";

function getClientIP(){

    if (!$_SERVER['HTTP_CLIENT_IP'])
         $ip = $_SERVER['REMOTE_ADDR']
    else
        $ip =$_SERVER['HTTP_CLIENT_IP'];
    return $ip;

}

Causes:

1. Invalid file type uploaded by the user your uploading (.doc when only .xls is allowed)
2. The file uploaded is not within the specified file types added in the upload config
3. Mime type error in codeigniter caused by the mime type of the extension does not match the mime type specified in /application/config/mimes.php

Start by checking what is the mime type of the file your uploading

$data = array('upload_data' => $this->upload->data());
$mimetype= $data['upload_data']['file_type'];
echo $mimetype;

then check in the mimes.php if that mime type matches the extension you want to upload

Example:
word document

'doc'	=>	'application/msword'

excel file has many mime types, if its missing just add it in the array

'xls'	=>	array('application/excel', 'application/vnd.ms-excel','application/x-msexcel')

$path = "/home/files/documents.doc";
   header("Cache-Control: pre-check=0, post-check=0, max-age=0");
   header('Content-Type: application/octet-stream');
   header("Content-Disposition: attachment; filename=documents.doc);
   header("Content-Description: File Transfer");
   header("Content-Type:documents.doc);
   header("Last-Modified: " . now());
echo readfile($path);

I somehow noticed php rand() has a pattern, So I dug up the php docs for a better rand function and end up discovering this neat random function

Use mt_rand()

<?php
echo mt_rand() . "\n";
echo mt_rand() . "\n";

echo mt_rand(5, 15);

?>

Output

1604716014
1478613278
6

I was able to figure out how to run Simple_html_dom php library on codeigniter

Download the simple html dom library here simple html dom

I copied the file Simple_html_dom.php to

/system/libraries

Then in my controller I call it using

require_once(‘Simple_html_dom.php’);

To use it, I initialized it using this line

$html = new Simple_html_dom();

Load a page or link using the line

$html->load_file(‘http://www.google.com’);

and parse or find elements using this line

$html->find(‘table tr td’)->plaintext;

works fine and fits right to what I needed to do.

Excel time looks like this 40179
You cannot compare or compute dates in PHP if it looks like that, it should be on unixtime
which looks like this 1104537600

Here is a quick function to convert excel date to unixtime date

<?
$DayDifference = 25569; //Day difference between 1 January 1900 to 1 January 1970
$Day2Seconds = 86400;// no. of seconds in a day
$ExcelTime = 30128;//integer value stored in the Excel column
$ExcelTime = substr($ExcelTime,0,5);//trim excel time get only whole 5 digit
$UnixTime = ($ExcelTime - $DayDifference)*$Day2Seconds;
echo $UnixTime;
?>

Solution:
Type this above the function you are trying to excute
ini_set(”memory_limit”,”16M”);
or any desired memory size you wish

This might cause the following error:
mysqlnd cannot connect to MySQL 4.1+ using old authentication

Solution:
type in mysql

SET PASSWORD FOR 'some_user'@'some_host' = OLD_PASSWORD('newpwd');

Findings:
Because mysqlnd has a bigger password hash it will not be compatible anymore with the password written beforehand.

Ref:
http://dev.mysql.com/doc/refman/5.1/en/old-client.html

In dealing with files on ci use the file helper
http://codeigniter.com/user_guide/helpers/file_helper.html

It is loaded using this line
$this->load->helper(‘file’);

read a file with read_file()
$data = read_file(‘./path/to/file.php’);

write a file with write_file();
write_file(‘./path/to/file.php’, $data, ‘w+’);

CI recommends “r+” but its better to use “w+”