Dopo aver fatto alcune ricerche sul web, ho scoperto che l'API del file JavaScript HTML5 è molto utile per leggere il contenuto dal file system locale. Ho scritto una piccola sceneggiatura e funziona perfettamente.
Per questo esempio, ho creato due file:
- indice.htm
- servizio.php
indice.htm
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Upload large CSV file</title>
<style>
body{font-size:8pt; color:#333}
#wrap{width:500px; margin:5px auto}
#responce{height:200px; overflow-y:scroll; border:1px solid #ddd;}
</style>
</head>
<body>
<div id="wrap">
<ul id="responce">
</ul><!-- // response -->
<input type="file" id="fileSelected"/>
<button id="btnUpload">Upload</button>
</div><!-- // wrap -->
<script
src="https://code.jquery.com/jquery-3.1.1.min.js"
integrity="sha256-hVVnYaiADRTO2PzUGmuLJr8BLUSjGIZsDYGmIJLv2b8="
crossorigin="anonymous"></script>
<script>
var reader_offset = 0; //current reader offset position
var buffer_size = 1024; //
var pending_content = '';
/**
* Read a chunk of data from current offset.
*/
function readAndSendChunk()
{
var reader = new FileReader();
var file = $('#fileSelected')[0].files[0];
reader.onloadend = function(evt){
//check for end of file
if(evt.loaded == 0) return;
//increse offset value
reader_offset += evt.loaded;
//check for only complete line
var last_line_end = evt.target.result.lastIndexOf('\n');
var content = pending_content + evt.target.result.substring(0, last_line_end);
pending_content = evt.target.result.substring(last_line_end+1, evt.target.result.length);
//upload data
send(content);
};
var blob = file.slice(reader_offset, reader_offset + buffer_size);
reader.readAsText(blob);
}
/**
* Send data to server using AJAX
*/
function send(data_chank)
{
$.ajax({
url: "service.php",
method: 'POST',
data: data_chank
}).done(function(response) {
//show responce message received from server
$( '#responce' ).append( '<li>' + response + '</li>');
//try for next chank
readAndSendChunk();
});
}
/**
* On page load
*/
$(function(){
$('#btnUpload').click(function(){
reader_offset = 0;
pending_content = '';
readAndSendChunk();
});
});
</script>
</body>
</html>servizio.php
<?php
$content = file_get_contents('php://input');
$lines = explode("\n", $content);
foreach($lines as $line){
$csv_row = str_getcsv($line);
//save data into database
//----
}
