PHP file or picture upload script tutorial and code

PHP file upload Script :: online picture upload

File upload is very common requirement of many web sites. Image upload is very common requirement and many sites are using this to allow members or visitors to upload files. This file upload script explained in a step by step way to accomplish this online uploading to a web server. We can even create thumbnail images of the uploaded image file by php.

The main requirement is to allow the members to browse the local computer and point to the file required for uploading.

Check the file if it is allowed for upload or not. We can check for file size, file extension, file name etc.
Copy the file to server.
Place the file in required directory and then give necessary file permission.

Before starting we must add file permission to the directory where we plan to store the files after uploading it. Let us give the directory name upload and give write permission to it. If it is a Window server nothing is required and by default window gives all permissions. For Linux and Uinx we have to give write (Chmod) permission to allow uploaded files to store.

If you are uploading large files then read about maximum file execution time allowed and its adjuestments.

Let us add the html code to show the browse button for the visitors to point to file required for uploading. Here is the code
upload.php

<form action='uploadck.php' method=post  enctype='multipart/form-data' >
Upload this file: <input type=file name='file_up'>
<input type=submit value='Upload Image'></FORM>

This html code will display a text box with file upload button. The form tag is bit different than the normal form tag used ( see the encrypte =).

In our php script we will get all details in a global variable like this.

$_FILES[file_up];

So to get the file size we have to use

$_FILES[file_up][size]

Note that in the form we have used the input filed name as file_up. Same way all other information can be collected from the global variable.

$_FILES[file_up][name]
$_FILES[file_up][size]
$_FILES[file_up][type]
$_FILES[file_up][tmp_name]
$_FILES[file_up][error]

Maximum allowed file upload size.

In PHP installation ( php.ini file )there is a file size limit for uploading files. You can check your php info to know about this upper limit. You can also run this code to read other parameters affecting your file upload.

<?Php
echo "Maximum allowed file size: ".ini_get('upload_max_filesize');
echo "<br>";
echo "Maximum input time : ".ini_get('max_input_time');
echo "<br>";
echo "Maximum execution time : ".ini_get('max_execution_time');
echo "<br>";
echo "Maximum Post size : ".ini_get('post_max_size');
?>

From this you can add a check in the script and display message to the user saying about the error. Here is the code for that.

if ($_FILES[file_up][size]>250000){
$msg=$msg."Your uploaded file size is more than 250KB so please reduce the file size and then upload.<BR>";
$file_upload="false";
}

Here is the full code to handle file upload.

<?Php
$file_upload_flag="true"; // Flag to check conditions
$file_up_size=$_FILES['file_up'][size];

echo "File Name:".$_FILES[file_up][name];
echo "<br>File Size:".$_FILES[file_up][size];
echo "<br>File Type:".$_FILES[file_up][type];
echo "<br>File tmp_name:".$_FILES[file_up][tmp_name];
echo "<br>File error:".$_FILES[file_up][error];
echo "<br>---End of uploaded file details---<br><br>";

if ($_FILES[file_up][size]>250000){
$msg=$msg."Your uploaded file size is more than 250KB ";
$msg.=" so please reduce the file size and then upload.<BR>";
$file_upload_flag="false";
}

// allow only jpeg or gif files, remove this if not required //
if (!($_FILES[file_up][type] =="image/jpeg" OR $_FILES[file_up][type] =="image/gif"))
{$msg=$msg."Your uploaded file must be of JPG or GIF. ";
$msg.="Other file types are not allowed<BR>";
$file_upload_flag="false";}

$file_name=$_FILES[file_up][name];
// the path with the file name where the file will be stored
$add="upload/$file_name"; 

if($file_upload_flag=="true"){ // checking the Flag value 

if(move_uploaded_file ($_FILES[file_up][tmp_name], $add)){
// do your coding here to give a thanks message or any other thing.
$msg="File successfully uploaded";
}else{
echo "Failed to upload file Contact Site admin to fix the problem";
}
}else{
$msg .= " Failed to upload file ";
}
echo " $msg <br><br> <a href=upload.php>Return to File upload </a>";
?>

Uploading file by using JQuery Ajax
Without refreshing pages we can upload files along with other input data by using multipart/form-data. The details we enter along with the uploaded file name can be stored in a MySQL database table.

How to Install and test

Download the zip file at the end of this page.
upload.php : HTML page showing upload button.
uploadck.php : PHP script to check & manage upload.
ini_text.php: Check your php.ini file settings.

Click here for More on PHP File functions