Php obtains the IP address of the client.

Simplest practice

The code is as follows:	Copy code
Function getRealIpAddr () { If (! Emptyempty ($ _ SERVER ['http _ CLIENT_IP '])   { $ Ip = $ _ SERVER ['http _ CLIENT_IP '];   } Elseif (! Emptyempty ($ _ SERVER ['http _ X_FORWARDED_FOR ']) // To check ip is pass from proxy   { $ Ip = $ _ SERVER ['http _ X_FORWARDED_FOR '];   } Else   { $ Ip = $ _ SERVER ['remote _ ADDR '];   } Return $ ip; }

I wrote this myself.

 

The code is as follows:

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<? Php If (getenv ('http _ CLIENT_IP ') & strcasecmp (getenv ('http _ CLIENT_IP'), 'Unknown ')){ $ Onlineip = getenv ('http _ CLIENT_IP '); } Elseif (getenv ('http _ X_FORWARDED_FOR ') & strcasecmp (getenv ('http _ X_FORWARDED_FOR'), 'Unknown ')){ $ Onlineip = getenv ('http _ X_FORWARDED_FOR '); } Elseif (getenv ('remote _ ADDR ') & strcasecmp (getenv ('remote _ ADDR'), 'Unknown ')){ $ Onlineip = getenv ('remote _ ADDR '); } Elseif (isset ($ _ SERVER ['remote _ ADDR ']) & $ _ SERVER ['remote _ ADDR '] & strcasecmp ($ _ SERVER ['remote _ ADDR'], 'Unknown ')){ $ Onlineip = $ _ SERVER ['remote _ ADDR '];  } Echo $ onlineip; ?>

However, Baidu found

Instance

The code is as follows:

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Function real_ip (){ Static $ realip = NULL; If ($ realip! = NULL ){ Return $ realip;  } If (isset ($ _ SERVER )){ If (isset ($ _ SERVER ['http _ X_FORWARDED_FOR ']) { $ Arr = explode (',', $ _ SERVER ['http _ X_FORWARDED_FOR ']); /* Obtain the first non-unknown valid IP string in X-Forwarded-*/ Foreach ($ arr AS $ ip ){ $ Ip = trim ($ ip ); If ($ ip! = 'Unknown '){ $ Realip = $ ip; Break;     }    } } Elseif (isset ($ _ SERVER ['http _ CLIENT_IP ']) { $ Realip = $ _ SERVER ['http _ CLIENT_IP ']; } Else { If (isset ($ _ SERVER ['remote _ ADDR ']) { $ Realip = $ _ SERVER ['remote _ ADDR ']; } Else { $ Realip = '0. 0.0.0 ';    }   } } Else { If (getenv ('http _ X_FORWARDED_FOR ')){ $ Realip = getenv ('http _ X_FORWARDED_FOR '); } Elseif (getenv ('http _ CLIENT_IP ')){ $ Realip = getenv ('http _ CLIENT_IP '); } Else { $ Realip = getenv ('remote _ ADDR ');   }  } Preg_match ("/[d.] {7, 15}/", $ realip, $ onlineip ); $ Realip =! Empty ($ onlineip [0])? $ Onlineip [0]: '0. 0.0.0 '; Return $ realip; }