Some usage of $ _ SERVER-PHP source code

Some usage of $ _ SERVER php code

// Obtain the domain name or HOST address echo $ _ SERVER ['http _ host']. ""; # localhost // Obtain the webpage address echo $ _ SERVER ['php _ SELF ']. ""; #/blog/testurl. php // Obtain the url parameter echo $ _ SERVER ["QUERY_STRING"]. ""; # id = 5 // obtain the user proxy echo $ _ SERVER ['http _ referer']. ""; // obtain the complete urlecho 'http ://'. $ _ SERVER ['http _ host']. $ _ SERVER ['request _ URI ']; echo 'http ://'. $ _ SERVER ['http _ host']. $ _ SERVER ['php _ SELF ']. '? '. $ _ SERVER ['query _ string']; # http: // localhost/blog/testurl. php? Id = 5 // Complete urlecho 'http: // 'containing the port number ://'. $ _ SERVER ['server _ name']. ':'. $ _ SERVER ["SERVER_PORT"]. $ _ SERVER ["REQUEST_URI"]; # http: // localhost: 80/blog/testurl. php? Id = 5 // only the path $ url = 'http ://'. $ _ SERVER ['server _ name']. $ _ SERVER ["REQUEST_URI"]; echo dirname ($ url); # http: // localhost/blog