Javascript PHP 将文件写入服务器

Question

I am using javascript to send data to php file on server, the php file will write the received data into a text file on server.

Javascript

var data = "data123";
var request = new XMLHttpRequest();
request.open('POST', 'http://......../save.php', true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
request.send(data);

PHP file on server

<?php
$test =$_GET['data'];
$file = 'people.txt';
// Open the file to get existing content
$current = file_get_contents($file);
// Append a new person to the file
$current .= $test;
// Write the contents back to the file
file_put_contents($file, $current);
?>

I tried the code above, but the text file didn't change.

Answer 1

You have two problems.

1. You are trying to read the data from $_GET which contains data from the query string and not the request body. Use $_POST
2. You are claiming to encode your data as application/x-www-form-urlencoded but are actually just sending text/plain . You need to encode the data.

eg

var key = "data";
var encodedData = encodeURIComponent(key) + "=" + encodeURIComponent(data);

request.send(encodedData);

Answer 2

Your are using POST method on your ajax request, so in your php use $_POST instead $_GET

$test =$_POST['data'];

And in your javascript use = into your string like :

var data = "data=123";

Answer 3

It doesn't seem like you "post" the data or set the parameter name "data" from your javascript. If you do

var_dump($_POST['data'])

I'm quite certain you will not get 'data123';

If you post data it will reside in " $_POST " and if you get data it will have to be fetched from " $_GET ". Or both are usually added to " $_REQUEST ".

Instead, you will have to set the names like

var params = 'data=data123';

and then send your params

http.send(params);

The fetch it from the correct array depending on if you send using get or post.

Answer 4

You have to send your data with a key

var data = encodeURIComponent("data123");
//...
request.send('data=' + data);

The PHP part should be as following:

<?php
$data = $_POST['data'];
$file = __DIR__ . '/people.txt'; //its not needed to add the dir
//use the FILE_APPEND flag to append your data its faster than loading the whole contents
file_put_contents($file, $data, FILE_APPEND);