The usage of header function in PHP and its notice _php example

void header (String $string [, bool $replace = true [, int $http _response_code]]): Send a raw HTTP header

Here are several uses of header:

1, use header function to jump page;

Header (' Location: '. $url);

Where $url is the URL that will jump.

　　The following considerations for this usage are:

location and ":" Can not have a space between, or there will be errors (note: I just tested, in my local environment, no jump page, but there is no error, not clear what the reason);

• No output before using header (note: This is known to all, if there is any output before header, including blank, there will be header already sent by xxx error);

The things behind the header will also be carried out;

2. Use Header statement Content-type

Header (' Content-type:text/html;charset=utf-8 ');
There is nothing to say about it;

3, use header return response status code

Header (sprintf ('%s%d%s ', $http _version, $status _code, $description));

The style is like this;

For example: Header (' http/1.1 404 Not Found ');

4. Use header to perform jump after a certain time

Header ("Refresh: {$delay}; url={$url} ");

Where $delay is the time to postpone the jump, $url to the URL that needs to jump

For example: Header (' refresh:10; url=http://www.example.org/'); Meaning 10s jump to http://www.eexample.org this site

5. Use header to control browser cache

Header ("Expires:mon, June June 1997 05:00:00 GMT");
Header ("last-modified:"). Gmdate ("D, D M Y h:i:s").　　"GMT");
Header ("Cache-control:no-cache, must-revalidate");
Header ("Pragma:no-cache");

6. Perform HTTP validation

Header (' http/1.1 401 Unauthorized ');
Header (' Www-authenticate:basic realm= "top Secret");

7. Use Header for download operation

Header (' Content-type:application/octet-stream ');/set the content type
header (' content-disposition:attachment; Filename= ') Example.zip "');　　Set MIME user to download as an attachment if you change the attachment to inline meaning to open
header (' content-transfer-encoding:binary ') online, set the transmission mode
Header (' Content-length: '. FileSize (' Example.zip '))//Set Content length
//load the file to send:
ReadFile (' Example.zip ' //Read files that need to be downloaded

Here are a few more examples of PHP header usage

Jump page

Header (' Location: '. $url); There are no spaces between location and ":".

Statement Content-type

Header (' Content-type:text/html;charset=utf-8 ');

Return response status Code

Header (' http/1.1 404 Not Found ');

To perform a jump after a certain time

Header (' refresh:10; url=http://www.baidu.com/'); 10s after the jump.

controlling browser caching

Header ("Expires:mon, June June 1997 05:00:00 GMT");
Header ("last-modified:"). Gmdate ("D, D M Y h:i:s"). "GMT");
Header ("Cache-control:no-cache, must-revalidate");
Header ("Pragma:no-cache");

Performing HTTP validation

Header (' http/1.1 401 Unauthorized ');
Header (' Www-authenticate:basic realm= "top Secret");

Perform a download operation

Header (' Content-type:application/octet-stream '); Set Content Type
Header (' content-disposition:attachment; filename= "Example.zip"); Set MIME user as Attachment
Header (' content-transfer-encoding:binary '); Set transport mode
Header (' Content-length: '. FileSize (' Example.zip ')); Set Content length