We can use CSV helper for exporting data in excelsheet in cakephp.

For using CSV helper we have to follow simple steps.

Step 1:- Firstly we have to create a file naming CsvHelper.php and have to save it in our app/view/Helper directory.

Below is the code which CsvHelper.php  file contain

<?php
class CsvHelper extends AppHelper
{
var $delimiter = ',';
var $enclosure = '"';
var $filename = 'Export.csv';
var $line = array();
var $buffer;

function CsvHelper()
{
    $this->clear();
}
function clear() 
{
    $this->line = array();
    $this->buffer = fopen('php://temp/maxmemory:'. (5*1024*1024), 'r+');
}

function addField($value) 
{
    $this->line[] = $value;
}

function endRow() 
{
    $this->addRow($this->line);
    $this->line = array();
}

function addRow($row) 
{
    fputcsv($this->buffer, $row, $this->delimiter, $this->enclosure);
}

function renderHeaders() 
{
    header('Content-Type: text/csv');
    header("Content-type:application/vnd.ms-excel");
    header("Content-disposition:attachment;filename=".$this->filename);
}

function setFilename($filename) 
{
    $this->filename = $filename;
    if (strtolower(substr($this->filename, -4)) != '.csv') 
    {
        $this->filename .= '.csv';
    }
}

function render($outputHeaders = true, $to_encoding = null, $from_encoding ="auto") 
{
    if ($outputHeaders) 
    {
        if (is_string($outputHeaders)) 
        {
            $this->setFilename($outputHeaders);
        }
        $this->renderHeaders();
    }
    rewind($this->buffer);
    $output = stream_get_contents($this->buffer);

    if ($to_encoding) 
    {
        $output = mb_convert_encoding($output, $to_encoding, $from_encoding);
    }
    return $this->output($output);
}
}
?>

Step 2:- Then we have add this CsvHelper  in our controller by using below code .

var $helpers = array('Html', 'Form','Csv'); 

Step 3:- Then we have to create export method in our controller which contains below code.

function export()
{
    $this->set('posts', $this->Post->find('all'));
    $this->layout = null;
    $this->autoLayout = false;
    Configure::write('debug','0');
}

Step 4:- Then we have to create ctp file for export function i.e export.ctp which contain below code .

<?php

$line= $posts[0]['Post'];
$this->CSV->addRow(array_keys($line));
 foreach ($posts as $post)
 {
   $line= $post['Post']; 
   $this->CSV->addRow($line);
 }
 $filename='posts';
 echo  $this->CSV->render($filename);
?>

Step 5:- Now we have to add link to  our view file by using below code. On this link click we will see our data in excelsheet  format.

<?php echo $this->Html->link('Export',array('controller'=>'posts','action'=>'export'), array('target'=>'_blank'));?>