Form data to CSV

FormCSV.php

<?php 

class CSVExport
{

	/**
	* Constructor
*/
	public function __construct()
	{
		if(isset($_GET['download_report']))
		{
			$csv = $this->generate_csv();

			header("Pragma: public");
			header("Expires: 0");
			header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
			header("Cache-Control: private", false);
			header("Content-Type: application/octet-stream");
			header("Content-Disposition: attachment; filename=\"muestra.csv\";" );
			header("Content-Transfer-Encoding: binary");

			echo $csv;
			exit;
		}

	// Add extra menu items for admins
		add_action('admin_menu', array($this, 'admin_menu'));

	// Create end-points
		add_filter('query_vars', array($this, 'query_vars'));
		add_action('parse_request', array($this, 'parse_request'));
	}

	/**
	* Add extra menu items for admins
	*/
	public function admin_menu()
	{
		add_menu_page('Download Report', 'Download Muestra Reports', 'manage_options', 'download_report', array($this, 'download_report'),"dashicons-welcome-view-site");
	}

	/**
	* Allow for custom query variables
*/
	public function query_vars($query_vars)
	{
		$query_vars[] = 'download_report';
		return $query_vars;
	}

	/**
	* Parse the request
*/
	public function parse_request(&$wp)
	{
		if(array_key_exists('download_report', $wp->query_vars))
		{
			$this->download_report();
			exit;
		}
	}

	/**
	* Download report
*/
	public function download_report()
	{
		echo '<div class="wrap">';
		echo '<div id="icon-tools" class="icon32">
	</div>';
	echo '<a href='.site_url().'/wp-admin/admin.php?download_report'.'  <h2>Download Muestra</h2>';
//$url = site_url();

}

/**
* Converting data to CSV
*/
public function generate_csv()
{
	global $wpdb;
	$csv_output = '';
	$table = 'wp-muestra';
	$query = "SHOW COLUMNS FROM ".$wpdb->prefix."muestra";
	$result = $wpdb->get_results($query);

	
	$i = 0;



	if (count($result) > 0) {
		foreach ($result as $key => $value) {
			
			$csv_output = $csv_output . $value->Field.",";
			
		$csv_output .= "\n";
	}

	

	$query = "SELECT * FROM ".$wpdb->prefix."muestra";
	$values = $wpdb->get_results($query);

	

	if (count($values)>0) {
		foreach ($values as $key => $value) {
			foreach ($value as $k => $v) {
				// echo "<pre>";
				// print_r($v);
				// echo "</pre>";	
				$csv_output .= $v.",";
			}
			$csv_output .= "\n";
		}
	}

	

	return $csv_output;
}




}

// Instantiate a singleton of this plugin
$csvExport = new CSVExport();

class CSVExportParticipa
{

	/**
	* Constructor
*/
	public function __construct()
	{
		if(isset($_GET['download_participa_report']))
		{
			$csv = $this->generate_csv();

			header("Pragma: public");
			header("Expires: 0");
			header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
			header("Cache-Control: private", false);
			header("Content-Type: application/octet-stream");
			header("Content-Disposition: attachment; filename=\"participa.csv\";" );
			header("Content-Transfer-Encoding: binary");

			echo $csv;
			exit;
		}

	// Add extra menu items for admins
		add_action('admin_menu', array($this, 'admin_menu'));

	// Create end-points
		add_filter('query_vars', array($this, 'query_vars'));
		add_action('parse_request', array($this, 'parse_request'));
	}

	/**
	* Add extra menu items for admins
	*/
	public function admin_menu()
	{
		add_menu_page('Download Report', 'Download Participa Reports', 'manage_options', 'download_participa_report', array($this, 'download_participa_report'),"dashicons-welcome-view-site");
	}

	/**
	* Allow for custom query variables
*/
	public function query_vars($query_vars)
	{
		$query_vars[] = 'download_participa_report';
		return $query_vars;
	}

	/**
	* Parse the request
*/
	public function parse_request(&$wp)
	{
		if(array_key_exists('download_participa_report', $wp->query_vars))
		{
			$this->download_participa_report();
			exit;
		}
	}

	/**
	* Download report
*/
	public function download_participa_report()
	{
		echo '<div class="wrap">';
		echo '<div id="icon-tools" class="icon32">
	</div>';
	echo '<a href='.site_url().'/wp-admin/admin.php?download_participa_report'.'  <h2>Download Participa</h2>';
//$url = site_url();

}

/**
* Converting data to CSV
*/
public function generate_csv()
{
	global $wpdb;
	$csv_output = '';
	$table = 'wp-participa';
	$query = "SHOW COLUMNS FROM ".$wpdb->prefix."participa";
	$result = $wpdb->get_results($query);

	
	$i = 0;

	if (count($result) > 0) {
		foreach ($result as $key => $value) {
			// echo "<pre>";
			// print_r( $value->Field);
			$csv_output = $csv_output . $value->Field.",";
			// echo "</pre>";
		}
		$csv_output .= "\n";
	}



	$query = "SELECT * FROM ".$wpdb->prefix."participa";
	$values = $wpdb->get_results($query);

	

	if (count($values)>0) {
		foreach ($values as $key => $value) {
			foreach ($value as $k => $v) {
				// echo "<pre>";
				// print_r($v);
				// echo "</pre>";	
				$csv_output .= $v.",";
			}
			$csv_output .= "\n";
		}
	}

	return $csv_output;
}




}

// Instantiate a singleton of this plugin
$csvExport = new CSVExportParticipa();


?>