PHP file upload and download source code,

PHP file upload and download source code,

　　I. File Upload

Front-end page:

<! DOCTYPE html> 
　　Background processing:
<? Php // receive and submit information sent on the page $ name = $ _ POST ['username']; $ intro =$ _ POST ['fileintro']; // $ _ FILES stores file-related information // echo "<pre>"; // print_r ($ _ FILES); // echo "</pre> "; // you can limit the file size here/* $ filesize = $ _ FILES ['myfile'] ['SIZE']; if ($ filesize> 2*1024*1024) {echo "the file is too large to be uploaded"; exit ();} * /// you can restrict the file type./* $ filetype = $ _ FILES ['myfile'] ['type']; if ($ filetype! = 'Image/jpg '& $ filetype! = 'Application/pdf ') {echo "file types can only be jpg and pdf"; exit ();} */if (is_uploaded_file ($ _ FILES ['myfile'] ['tmp _ name']) {// save the file to the directory you want to store $ uploaded = $ _ FILES ['myfile'] ['tmp _ name']; // each user dynamically creates a folder $ userpath =$ _ SERVER ['document _ root']. "/up /". $ name; // determine whether the user already has a folder if (! File_exists ($ userpath) {mkdir ($ userpath);} // prevents the same user from uploading files of the same name. You can add a timestamp to the file. // $ Moveto = $ userpath. "/". time (). $ _ FILES ['myfile'] ['name']; // or modify the file name, however, the file suffix $ truename = $ _ FILES ['myfile'] ['name']; $ moveto = $ userpath must be used for string processing. "/". time (). substr ($ truename, strrpos ($ truename ,". "); if (move_uploaded_file ($ uploaded, iconv (" UTF-8 "," gb2312 ", $ moveto) {echo" Upload File ". $ _ FILES ['myfile'] ['name']. "succeeded";} else {echo "uploading files ". $ _ FILES ['myfile'] ['name']. "failed" ;}} else {echo "Upload File ". $ FILES ['myfi Le '] ['name']. "failed" ;}?>
　　Ii. File Download:
Single file download:
<? Php function down_file ($ file_name, $ file_path) {// $ file_name = iconv ("uft-8", "gb2312", $ file_name); // if the file name is Chinese, you need to transcode the Chinese name gb2312 // the file to be downloaded and read to the server's memory // The server returns the file data to the browser // the browser writes the file to the specified location // 1. determine whether the object exists if (! File_exists ($ file_name) {echo "111"; return ;}$ fp = fopen ($ file_name, "r"); $ file_size = filesize ($ file_name ); // get the file size // you can use file_size to limit the size of the file downloaded by the browser. // The returned File header ("Content-type: application/octet-stream"); // The returned header ("Accept-Ranges: bytes") in bytes "); // return the file size header ("Accept-Length: $ file_size"); // In the displayed dialog box, the corresponding file name header ("Content-Disposition: attachment; filename = ". $ file_name); $ buffer = 1024; // defines the buffer // for download security, it is best to use the file byte read counter $ file_count = 0; // feof is used to determine whether the file is read to the end of the document while (! Feof ($ fp) & ($ file_size-$ file_count> 0) {$ file_data = fread ($ fp, $ buffer ); // count the number of bytes read $ file_count + $ buffer; echo $ file_data; // send some data to the browser} fclose ($ fp); // close the file}?>
　　Download multiple files:
DownList. php:
<a href="downprocess.php?filename=1.jpg">down</a><br><br><a href="downprocess.php?filename=2.jpg">down</a><br><br><a href="downprocess.php?filename=3.jpg">down</a><br><br><a href="downprocess.php?filename=4.jpg">down</a><br><br>
　　Downprocess. php:
<? Php $ filename = $ _ REQUEST ['filename']; function down_file ($ file_name) {if (! File_exists ($ file_name) {echo "111"; return ;}$ fp = fopen ($ file_name, "r"); $ file_size = filesize ($ file_name ); header ("Content-type: application/octet-stream"); // return header ("Accept-Ranges: bytes") in bytes "); // return the file size header ("Accept-Length: $ file_size"); // In the displayed dialog box, the corresponding file name header ("Content-Disposition: attachment; filename = ". $ file_name); $ buffer = 1024; // defines the buffer $ file_count = 0; // feof is used to determine whether the file is read to the end of the document while (! Feof ($ fp) & ($ file_size-$ file_count> 0) {$ file_data = fread ($ fp, $ buffer ); // count the number of bytes read $ file_count + $ buffer; echo $ file_data; // send some data to the browser} fclose ($ fp );} down_file ($ filename);?>