<?php
class CSVData
{
	public $colDelimiter = ';';
	
	public function __construct($colDelimiter = ';')
	{
		$this->colDelimiter = $colDelimiter;
	}
	/**
	 * Converts an array of data to CSV format.
	 * 
	 * @param string $head The CSV header. Example: array('User id', 'User Name', 'User Email');
	 * @param string $data The CSV data. Example:
	 * array(
	 *   array(1, 'John',   '[email protected]'  ),
	 *   array(2, 'Andrew', '[email protected]'),
	 *   array(3, 'Ana',    '[email protected]'  )
	 * );
	 * @return string The Proper formatted CSV string
	 */
	public function arrayToCSV($head, $data)
	{
		$csv = '';
		array_unshift($data, $head);
		foreach($data as $d) $csv .= implode($this->colDelimiter, array_map(array($this, '_quoteStr'), $d)) . "\n";
		return $csv;
	}
	/**
	 * Downloads CSV string to client as a file
	 * @param string $csv A properly formatted CSV string
	 * @param string $fileName Name of the file to be downloaded. Example: 'mycsv'
	 * @param bool $noCache [Optional] If true, headers will be sent to prevent
	 * browser caching of the CSV.
	 */
	public function downloadCSV($csv, $fileName, $noCache = false)
	{
		$len = strlen($csv);
		
		if($noCache) $this->_noCacheHeaders();
		header("Content-Type: text/csv");
		header("Content-Disposition: attachment; filename=\"{$fileName}.csv\";");
		header('Content-Transfer-Encoding: binary');
		header("Content-Length: {$len}");
		echo $csv;
	}
	/**
	 * Saves a CSV string as a CSV file in the server
	 * @param string $csv A properly formatted CSV string
	 * @param string $path Where to save the file. Example: archives/csv/.
	 * Notice the / at the end of the path.
	 * @param string $fileName Name of the file to be saved. Example: 'mycsv'
	 */
	public function saveCSV($csv, $path, $fileName)
	{
		$handle = fopen($path . $fileName . '.csv', 'w');
		if($handle === false) throw new Exception(
			'Could not create file: ' . $path . $fileName . '.csv'
		);
		fwrite($handle, $csv);
		fclose($handle);
	}
	//////////////////////////////////////////////////////////////////////////////////////////
	//PRIVATES
	//////////////////////////////////////////////////////////////////////////////////////////
	/** Quotes CSV column if necessary. */
	private function _quoteStr($str)
	{
		if(strpos($str, '"') !== false || strpos($str, $this->colDelimiter) !== false)
		{
			$str = '"' . str_replace('"', '""', $str) . '"';
		}
		return $str;
	}
	/** Sends no caching headers to browser. */
	private function _noCacheHeaders()
	{
		header('Expires: Mon, 26 Jul 1997 05:00:00 GMT'); //Date in the past
		header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . ' GMT'); //Now
		header('Cache-Control: no-store, no-cache, must-revalidate');
		header('Cache-Control: post-check=0, pre-check=0', false);
		header('Pragma: no-cache');
	}
}

//Usage of class
$head = array('User id', 'User Name', 'User Email'); //The head will probably be static
$data = array( //This data could be grabbed from a database
	array(1,  'John',      '[email protected]'      ),
	array(2,  'Andrew',    '[email protected]'    ),
	array(3,  'Ana',       '[email protected]'      ),
	array(4,  'Carlos',    '[email protected]'   ),
	array(5,  'Christina', '[email protected]'),
	array(6,  'Zed',       '[email protected]'      ),
	array(7,  'Nina',      '[email protected]'     ),
	array(8,  'Gabriela',  '[email protected]' ),
	array(9,  'Joseph',    '[email protected]'   ),
	array(10, 'Ariel',     '[email protected]'    )
);

$csv = new CSVData(); //Create a new instance
//Transform the array to CSV string
$csvStr = $csv->arrayToCSV($head, $data);
//Download CSV, the browser will prompt
//the user to download the file
$csv->downloadCSV($csvStr, 'users', true);
//Whrite csv data to the server
$csv->saveCSV($csvStr, 'archives/csv/', 'users');
?>

Class that convert arrays to csv format, downloads CSV files and saves to disk on server.

CSV handler class

class, download, csv

PHP