Php defines the 404 page method

First take a look at the PHP instance code: @ header (& quot; http11404notfound & quot;); @ header (& quot; status: 404 notfound & quot;); echo & amp; 39; echo404 & amp; 39; exit (); check whether 404 is set successfully

Let's take a look at the PHP instance code:

1. @ Header ("http/1.1 404 not found ");
2. @ Header ("status: 404 not found ");
3. Echo 'echo 404 ';
4. Exit ();

To check whether 404 is set successfully, you can use the firebug plug-in of firefox to check the setting:

When firebug has been installed, open the 404 status code page in the firefox browser and click the bug icon in the lower right corner to start the "network" tag, open "network-all/html-headers" in sequence. if everything is normal, you can see the page parameters including headers and responses.

404 page impact on the website:

The effect on seo is not great, but there is always better than not. if you have this permission, you 'd better set the 404 page, which is similar to the website location, not all websites have to be set, but sometimes they need to be set.

If you want to set a 404 page, you should consider the user experience rather than seo.

Apache 404 definition:

In apache, setting the 404 error page to set the 404 error page for apache server is simple. you only need to add the following content to the. htaccess file: errordocument 404/notfound. php