Saving RGraph charts to local machine - php

Question

I am having issues saving images to local file. Every other things look fine but the image won't just save. Here is a snippet of my code.
function saveImage(){
var xmlhttp;
xmlhttp=((window.XMLHttpRequest)?new XMLHttpRequest():new ActiveXObject("Microsoft.XMLHTTP"));
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
//do something with the response
}
}
xmlhttp.open("POST","ajxstuff.php",true);
var oldCanvas = document.getElementById('cvs').toDataURL("image/png");
var img = new Image();
img.src = oldCanvas;
xmlhttp.setRequestHeader("Content-type", "application/upload")
xmlhttp.send(oldCanvas);
}
Here is the the ajxstuff.php
<?php
if (isset($GLOBALS["HTTP_RAW_POST_DATA"]))
{
// Get the data like you would with traditional post
$rawImage=$GLOBALS['HTTP_RAW_POST_DATA'];
// Remove the headers
$removeHeaders=substr($rawImage, strpos($rawImage, ",")+1);
// decode it from base 64 and into image data only
$decode=base64_decode($removeHeaders);
// save to your server
$saveName = 'C:\Users\Administrator\Downloads\image009.png';
$fopen = fopen($saveName, 'wb' );
fwrite( $fopen, $decode);
fclose( $fopen );
}
?>

Answer 1

OK, here's my revised answer: You could instead of sending the image as (what looks like) a file, send it as text - since that's what you get from toDataUrl() (a base64 encoded representation of the image).
$.post('ajxstuff.php',{
myChart: document.getElementById('cvs').toDataURL()
}, function ()
{
/* callback */
})
And in your PHP script the data would show up in $_POST['myChart'] - and you could write it to a file like this:
<?php
$data = base64_decode($_POST['myChart']);
file_put_contents('C:\Users\Administrator\Downloads\image009.png', $data);
?>