PHP File Upload

On the server, Judge:

1) receive data post 2)enctype= "Multipart/form-data" Property

3) Move_uploaded_file: Move the file to the specified location

PHP.ini Temporary file configuration File_uploads = on upload_tmp_dir = "

Vanishing time for temporary files: temporary files disappear immediately after the. php file is accepted.

If not, the contents of the temporary file can be observed when the PHP file is not finished;

The client determines the size of the upload file: JS is not allowed to manipulate local files

Ajax is unable to determine the size of the uploaded file at the client

1.php File Upload process:

To do a file upload form:

<form action= "up.php" method= "POST" >
User name: <input type= "text" name= "username"/><br/>
Avatar: <input type= "file" name= "Pic"/><br/>
<input type= "Submit" value= "Submission"/>
</form>

1) After submission, the file is automatically sent to the server, forming a temporary file,

2) on the server, just need to move the temporary files to their desired location, you can complete the upload file

After PHP forms a temporary file, it also forms a $_files super global array

The array holds the temporary address, temporary name, size, and other information of the file.

Note: File upload must be submitted with post

In the up.php:

<?php
Print_r ($_files);
?>

An empty array is printed on the browser at this time

WORKAROUND: Declare the ENCTYPE option

That is: Declare in form: Enctype= "Multipart/form-data" property

Notifies the other server of the binary information form data that contains the file

It will appear:

{

Name: Upload file name

Type: File type

Tem_name: Temporary file name

Error: Fault code

Size: The file size is expressed in bytes;

}

3) How to move the uploaded temporary files

Using the Move_uploaded_file () function <?php

Print_r ($_files);

if (Move_uploaded_file ($_files[' pic '] [' tmp_name '], './file/'. $_files[' pic ' [' name '])) {
echo "Success";
}else{
echo "fail";

}

PHP File Upload