What is the difference between getcsv() and getcsvfile() methods in magento?

Question

I am trying to Export the AdminHtml Grids to the CSV. I have foud two methods getCsv() and getCsvFile() for Exporting results grid into CSV file. Could you please anyone tell me what is the difference between these two functions?

Method -1

$fileName = "filename.csv";
$content    = $this->getLayout()->createBlock('custom_modelue/adminhtml_report_grid')
            ->getCsv();
$this->_prepareDownloadResponse($fileName, $content);

Method -2

$fileName = "filename.csv";
$content    = $this->getLayout()->createBlock('custom_modelue/adminhtml_report_grid')
            ->getCsvFile();
$this->_prepareDownloadResponse($fileName, $content);

When i use Method -1 The Filters not get applied for the Export CSV Results. But in Method -2, The Filters are aplied to the resultset.

Answer 1

There difference between getCsv() and getCsvFile() is below

get CsvFile() is 

     Retrieve a file container array by grid data as CSV

     Return array with keys type and value

     return array

getcsvFile used to export grid contain to an csv in magen to system in most of cases

  and getCsv() is 
    Retrieve Grid data as CSV
    and return string

Answer 2

These are different functions, but with quite similar result.

getCsv() is defined at Mage\Adminhtml\Block\Report\Grid.php

getCsvFile() is defined at Mage\Adminhtml\Block\Widget\Grid.php