PHP upload files are often encountered in a number of problems summed up it, later use when not to look for.
1. Make a simple upload file first
Copy Code code as follows:
<meta http-equiv= "Content-type" content= "text/html; Charset=utf-8 ">
<body>
<form action= "upload_file.php" method= "POST"
Enctype= "Multipart/form-data" >
<label for= "File" >Filename:</label>
<input type= "File" name= "file" id= "file"/>
<br/>
<input type= "Submit" name= "submit" value= "Submit"/>
</form>
</body>
Copy Code code as follows:
<?php
if ($_files["file" ["Size"] < 20000)
{
if ($_files["file"] ["error"] > 0)
{
echo "Return Code:". $_files["File" ["Error"]. "<br/>";
}
Else
{
echo "Upload:". $_files["File" ["Name"]. "<br/>";
echo "Type:". $_files["File" ["type"]. "<br/>";
echo "Size:". ($_files["File"] ["size"]/1024). "Kb<br/>";
echo "Temp file:". $_files["File" ["Tmp_name"]. "<br/>";
if (file_exists ("upload/". $_files["File" ["Name"])
{
echo $_files["File" ["Name"]. "already exists."
}
Else
{
Move_uploaded_file ($_files["file"] ["Tmp_name"],
"Upload/". $_files["File" ["name"]);
echo "Stored in:". Upload/". $_files["File" ["Name"];
}
}
}
Else
{
echo "Invalid file";
}
?>
2. Then understand the value of the Super global variable $_files
Copy Code code as follows:
$_files[' UserFile ' [' Name ']
$_files[' userfile ' [' type ']
$_files[' userfile ' [' Size ']
$_files[' UserFile ' [' Tmp_name ']
$_files[' userfile ' [' Error ']
where all values of $_files[' userfile ' [' Error '] are:
UPLOAD_ERR_OK its value is 0, no error occurred, file upload success.
Upload_err_ini_size the value is 1, the uploaded file exceeds the upload_max_filesize option limit in php.ini.
Upload_err_form_size the value is 2, the size of the upload file exceeds the value specified by the Max_file_size option in the HTML form.
Upload_err_partial its value is 3, the file is only partially uploaded.
Upload_err_no_file has a value of 4 and no files are uploaded.
Upload_err_no_tmp_dir The value is 6, the temporary folder cannot be found. PHP 4.3.10 and PHP 5.0.3 introduced.
Upload_err_cant_write The value is 7, the file write failed. PHP 5.1.0 introduced.
3. Many situations: the need to strictly determine the upload file type
We know that it is unwise to use $_files[' userfile ' [' type '] to judge the type of upload file, because it is based on the suffix name of the file, and anyone can change the suffix of a mp3 file into JPG to disguise it as a picture upload, So PHP official proposed to use PHP extension php_fileinfo to judge the file mime, open the way to expand Baidu there are a lot of, win and Linux slightly different.
4. Scenario One: automatically rename after uploading files with duplicate names
Copy Code code as follows:
if (File_exists ("./upload/". $_files["File" ["Name"])
{
do{
$suffix = "";
$suffix _length = 4;
$str = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
$len = strlen ($str)-1;
Append 4 random characters after file name
for ($i =0; $i < $suffix _length; $i + +) {
$suffix. = $str [rand (0, $len)];
}
$upload _filename = $_files[' file ' [' Name '];
$filename = substr ($upload _filename,0,strrpos ($upload _filename, ".")). $suffix. "." substr ($upload _filename,strrpos ($_files["file"] ["name"], ".") +1);
}while (File_exists ("./upload/". $filename));
Move_uploaded_file ($_files["file"] ["Tmp_name"], "./upload/". $filename);
}else{
Move_uploaded_file ($_files["file"] ["Tmp_name"], "upload/". $_files["File" ["name"]);
}
5. Scenario Two: upload files according to the date catalogue
Copy Code code as follows:
$structure = './'. Date ("Y"). ' /'. Date ("M"). ' /'. Date ("D"). ' /';
if (!mkdir ($structure, 0777, True)) {
Die (' Failed to create folders ... ');
}
Move_uploaded_file ($_files["file"] ["Tmp_name"], $structure. $_files["File" ["name"]);
6. Scenario Three: multiple file uploads
Copy Code code as follows:
<form action= "" method= "Post" enctype= "Multipart/form-data" >
<p>pictures:
<input type= "File" Name= "pictures[]"/>
<input type= "File" Name= "pictures[]"/>
<input type= "File" Name= "pictures[]"/>
<input type= "Submit" value= "Send"/>
</p>
</form>
Copy Code code as follows:
<?php
foreach ($_files["Pictures"] ["error"] as $key => $error) {
if ($error = = UPLOAD_ERR_OK) {
$tmp _name = $_files["Pictures" ["Tmp_name"] [$key];
$name = $_files["Pictures" ["Name"] [$key];
Move_uploaded_file ($tmp _name, "data/$name");
}
}
?>
In some cases, this variable structure of multiple files is not easy to use:
Copy Code code as follows:
Array (1) {
["Upload"]=>array (2) {
[' Name ']=>array (2) {
[0]=>string (9) "File0.txt"
[1]=>string (9) "File1.txt"
}
[' Type ']=>array (2) {
[0]=>string (Text/plain)
[1]=>string (text/html)
}
}
}
In many cases, we need a structure like this.
Copy Code code as follows:
Array (1) {
["Upload"]=>array (2) {
[0]=>array (2) {
[' Name ']=>string (9) ' File0.txt '
[' Type ']=>string (Text/plain]
},
[1]=>array (2) {
[' Name ']=>string (9) ' File1.txt '
[' Type ']=>string (text/html]
}
}
}
You can easily transform the structure using the following function
Copy Code code as follows:
function Diverse_array ($vector) {
$result = Array ();
foreach ($vector as $key 1 => $value 1)
foreach ($value 1 as $key 2 => $value 2)
$result [$key 2][$key 1] = $value 2;
return $result;
}
$upload = Diverse_array ($_files["upload"]);
7. Sometimes: need to configure the server to modify the maximum upload file size
First, on the form
<input type= "hidden" name= "max_file_size" value= "bytes"/>
You can limit the size of the upload file (can be bypassed).
Then you need to adjust the configuration on the server
Ini:
Max_execution_time = 30 Maximum time per script to run, in seconds
Max_input_time = 60, the time each script can consume, the unit is also seconds
Memory_limit = 128M, which is the maximum memory consumed by the script
Post_max_size = 8M, form submission maximum data is 8M, this is not to limit the size of uploading individual files, but to the entire form of submission data restrictions.
Upload_max_filesize = 2M, maximum allowable size of uploaded file
Nginx:
Copy Code code as follows:
Location/{
root HTML;
Index index.html index.htm;
Client_max_body_size 1000m;
}
The above is the common problem of the treatment method, I hope you can enjoy.
