Php implements code for downloading files and garbled characters in file names

Recently, someone asked me how to download files. The php method is as follows:
Copy codeThe Code is as follows:
<? Php
Header ("Content-Type: application/force-download ");
Header ("Content-Disposition: attachment; filename=ins.jpg ");
Readfile ("imgs/test_Zoom.jpg ");
?>

The first line of code is forced download;
The second line of code specifies a name for the downloaded content;
The third line of code is to read the downloaded content into the file.
How to solve garbled characters in the PHP download file name
By setting Content-Type to application/octet-stream, you can download the dynamically generated Content as an object. You can use Content-Disposition to set the downloaded file name. Basically, download programs are written like this:
Copy codeThe Code is as follows:
<? Php
$ Filename = "document.txt ";
Header ('content-Type: application/octet-stream ');
Header ('content-Disposition: attachment; filename = '. $ filename );
Print "Hello! ";
?>

After the browser is opened, you can download document.txt.
However, if $ filename is UTF-8 encoded, Some browsers won't be able to handle it. For example, change the above program slightly:
Copy codeThe Code is as follows:
<? Php
$ Filename = "Chinese file name .txt ";
Header ('content-Type: application/octet-stream ');
Header ('content-Disposition: attachment; filename = '. $ filename );
Print "Hello! ";
?>

Save the program as a UTF-8 code and then access, IE6 download file name will be garbled. The file name downloaded under FF3 is only in Chinese. Everything works normally in Opera 9.
The output header is actually like this:
Content-Disposition: attachment; filename = Chinese file name. txt is defined according to RFC2231. The multi-language encoding Content-Disposition should be defined as follows:
Copy codeThe Code is as follows:
Content-Disposition: attachment; filename * = "attachment"

That is:
Add the equal sign after filename *
The filename value is divided into three sections by single quotes, which are character set (utf8), language (null), and URL code file names.
It is best to add double quotation marks. Otherwise, the content after the space in the file name cannot be displayed in Firefox.
Note that the urlencode result is not the same as the urlencode function result of php. The urlencode of php will replace the space with +, and replace it with % 20 here.
After experiments, we found that the support for several mainstream browsers is as follows:
IE6 attachment; filename = "<URL-encoded UTF-8 File Name>"
FF3 attachment; filename = "UTF-8 file name"
Attachment; filename * = "utf8'' <URL-encoded UTF-8 File Name>"
O9 attachment; filename = "UTF-8 file name"
Does Safari3 (Win) seem to be unsupported? None of the above methods works.
In this case, the program must be written in this way to support all mainstream browsers:
Copy codeThe Code is as follows:
<? Php
$ Ua = $ _ SERVER ["HTTP_USER_AGENT"];
$ Filename = "Chinese file name .txt ";
$ Encoded_filename = urlencode ($ filename );
$ Encoded_filename = str_replace ("+", "% 20", $ encoded_filename );
Header ('content-Type: application/octet-stream ');
If (preg_match ("/MSIE/", $ ua )){
Header ('content-Disposition: attachment; filename = "'. $ encoded_filename .'"');
} Else if (preg_match ("/Firefox/", $ ua )){
Header ('content-Disposition: attachment; filename * = "utf8 \ '\''. $ filename .'"');
} Else {
Header ('content-Disposition: attachment; filename = "'. $ filename .'"');
}
Print 'abc ';
?>