Redirect in PHP - Show txt file content - php

Question

I'm just learning to code and I don't know my way around yet.
I already know how to redirect to another page with php.
for example you go to http://example.com/test.php/ then you are redirected to http://example.com/test.txt with the following code:
"header('Location: http://example.com/test.txt);"
But now I'm not sure how to show the content of different files on your domain if the requested url has
?data=1 or ?seid=2 after the php. For example:
"http://example.com/test.php?data=request1" shows the text from
"http://example.com/test1.txt"
"http://example.com/test.php?data=request2" shows the text from
"http://example.com/test2.txt"
Have informed me so far that I have found something with $DataArray but don't know exactly how to use it? I tried something with it:
<?php
$DataArray = array(
"request1" => "test1",
"request2" => "test2"
if(isset($_GET['data'])) {
$data = str_replace(" ", "+", $_GET["data"]);
if(array_key_exists($data, $DataArray))
echo trim(json_decode(file_get_contents('data/'. $DataArray[$data] .'.txt'),JSON_UNESCAPED_SLASHES), '"');
else
echo "badrequest";
}
?>
Sadly that doesn't work for me so I don't know how to manage that.
edit: was able to fix it thanks for your help.
result:
<?php
$targets = array("1" => "http://redirect-new.com/", "2" => "http://redirect-old.com/", /* ... */);
if (isset($_GET["data"]) && array_key_exists($_GET["data"], $targets)) {
header("Location: {$targets[$_GET["data"]]}");
exit;
}
?>

Answer 1

Pass the file name in the link without using the extension and try this code:
if(isset($_GET['data']))
{
$data = $_GET['data'];
$filename = $data.'.txt'; // here we will get the name of the file with the extension (.Text)
$FilePath = '/www/path/to/file'; // your directory files here
$Link = $FilePath.'/'.$filename;
/*
* Here we will find out whether the file exists or not :
*/
// if use include :
if(file_exists($Link)){
include $Link;
}else{
print 'No File Exist !';
}
// if use header location
if(file_exists($Link)){
header('Location: http://example.com/'.$Link);
}else{
print 'No File Exist !';
}
}
This will work with you, but you should read more about the HTTP protocol It will benefit you more in the future .

Answer 2

You need to learn a few things, let me try to help you complete a 'reading list' that will help you to understand what you're trying to do and how to do it.
First, you want to learn your way around HTTP protocol. It's a basic knowledge that will get you far - it's great to be aware of this protocol - it will help you identify what you need in different scenarios.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Overview
pay attention to http messages part.
Then, see how PHP abstracts different parts of HTTP protocol, here's the GET parameters:
https://www.php.net/manual/en/reserved.variables.get.php - something you will have to make use of.
Also you'll have to read files: https://www.php.net/manual/en/function.file-get-contents.php