PHP file download details

This article describes in detail the principles of php download implementation, the specific implementation code, the possible problems, and the code sharing for file download implemented in other ways, for more information, see 1. php download schematic

2. file download source code:

The code is as follows:

<? Php
$ File_name = "haha.jpg"; // file to be downloaded
$ File_name = iconv ("UTF-8", "gb2312", "$ file_name ");
$ Fp = fopen ($ file_name, "r +"); // to download a file, you must first open the file and write it to the memory.
If (! File_exists ($ file_name) {// checks whether a file exists.
Echo "the file does not exist ";
Exit ();
}
$ File_size = filesize ("a.jpg"); // you can specify the file size.
// Returned file
Header ("Content-type: application/octet-stream ");
// Return in byte format
Header ("Accept-Ranges: bytes ");
// Returns the file size.
Header ("Accept-Length:". $ file_size );
// The client dialog box appears, with the corresponding file name
Header ("Content-Disposition: attachment; filename =". $ file_name );
// Prevents instantaneous server load increases and reads data in segments
$ Buffer = 1024;
While (! Feof ($ fp )){
$ File_data = fread ($ fp, $ buffer );
Echo $ file_data;
}
// Close the file
Fclose ($ fp );
?>

3. Solution to file encoding problems:

If the file name is Chinese, php functions cannot recognize the Chinese file name. generally, if the program code is UTF-8, php functions are old and can only recognize the Chinese characters encoded in gb2312, therefore, the iconv ("original encoding", "encoding to be converted", and "string to be transcoded") function can be used for transcoding.

For example, transcode a string from UTF-8 to gb2312

$ File_name = iconv ("UTF-8", "gb2312", "$ file_name ");

4. use the header method to download the source code.

The attached download method is encapsulated and can be used directly:

The code is as follows:

Function download_by_path ($ path_name, $ save_name ){
Ob_end_clean ();
$ Hfile = fopen ($ path_name, "rb") or die ("Can not find file: $ path_name \ n ");
Header ("Content-type: application/octet-stream ");
Header ("Content-Transfer-Encoding: binary ");
Header ("Accept-Ranges: bytes ");
Header ("Content-Length:". filesize ($ path_name ));
Header ("Content-Disposition: attachment; filename = \" $ save_name \"");
While (! Feof ($ hfile )){
Echo fread ($ hfile, 32768 );
}
Fclose ($ hfile );
}

The above is all the content in this article. do you have a preliminary understanding of php file download? I will try more on my own and use the simple example given in this article, make your project more complete.