A brief analysis on the method of uploading files in php

Notice:

tag, when implementing file upload, must be specified as multipart/form-data. In addition, pay attention to the hidden value field of the form option MAX_FILE_SIZE in the file upload.html. You can limit the size of the uploaded file by setting its Value. The value of MAX_FILE_SIZE is just a suggestion for browsers, in fact it can be easily bypassed. The maximum upload file size in PHP settings will not be invalid. However, it is better to add MAX_FILE_SIZE to the form to improve the upload experience.

2, upload.php

$f=&$HTTP_POST_FILES['Myfile'];
$dest_dir='uploads'; //Set the upload directory
$dest=$dest_dir.'/'.date( "ymd")."_".$f['name']; //Set the file name with the date plus the file name to avoid duplication
$r=move_uploaded_file($f['tmp_name'],$dest);
chmod ($dest, 0755); //Set the attributes of the uploaded file
 or

In the above example, the contents of the $_FILES array are as follows. Assume that the name of the file upload field is userfile (the name can be whatever you want)

$_FILES[’userfile’][’name’] The original name of the client machine file. $_FILES[’userfile’][’type’] The MIME type of the file, which requires the browser to provide support for this information, such as “image/gif”. $_FILES[’userfile’][’size’] The size of the uploaded file, in bytes. $_FILES[’userfile’][’tmp_name’] The temporary file name stored on the server after the file is uploaded. $_FILES[’userfile’][’error’] Error codes related to the file upload Value: 0; No errors occurred and the file was uploaded successfully. Value: 1; The uploaded file exceeds the limit of the upload_max_filesize option in php.ini. Value: 2; The size of the uploaded file exceeds the value specified by the MAX_FILE_SIZE option in the HTML form. Value: 3; Only part of the file was uploaded. Value: 4; No files were uploaded.