PhpIP get City API (pure IP database)-php Tutorial

PhpIP retrieval City API (pure IP database)

/** * Obtain the city name pure IP database based on the IP address * Edit: bbs.it-home.org */ Function convertip ($ ip ){ // IP data file path $ Dat_path = 'qqwry. Dat '; // Check the IP address If (! Filter_var ($ ip, FILTER_VALIDATE_IP )){ Return 'IP Address error '; } // Open the IP data file If (! $ Fd = @ fopen ($ dat_path, 'RB ')){ Return 'IP date file not exists or access denied '; } // Calculate the number of integers by decomposing IP addresses. $ IpNum = ip2long ($ ip ); // Obtain the start and end locations of the IP address data index. $ DataBegin = fread ($ fd, 4 ); $ DataEnd = fread ($ fd, 4 ); $ Ipbegin = implode ('', unpack ('L', $ DataBegin )); If ($ ipbegin <0) $ ipbegin + = pow (2, 32 ); $ Ipend = implode ('', unpack ('L', $ DataEnd )); If ($ ipend <0) $ ipend + = pow (2, 32); $ ipAllNum = ($ ipend-$ ipbegin)/7 + 1; $ BeginNum = 0; $ EndNum = $ ipAllNum; // use the binary search method to search for matched IP records from the index records while ($ ip1num> $ ipNum | $ ip2num <$ ipNum ){ $ Middle = intval ($ EndNum + $ BeginNum)/2 ); // Read 4 bytes from the offset pointer to the index position Fseek ($ fd, $ ipbegin + 7 * $ Middle ); $ IpData1 = fread ($ fd, 4 ); If (strlen ($ ipData1) <4 ){ Fclose ($ fd ); Return 'system error '; } // The extracted data is converted into an integer. if the data is negative, the power of 2 is added. $ Ip1num = implode ('', unpack ('L', $ ipData1 )); If ($ ip1num <0) $ ip1num + = pow (2, 32 ); // if the number of extracted long integers is greater than our IP address, modify the end position for the next loop if ($ ip1num> $ ipNum ){ $ EndNum = $ Middle; Continue; } // Obtain the next index after obtaining the previous index $ DataSeek = fread ($ fd, 3 ); If (strlen ($ DataSeek) <3 ){ Fclose ($ fd ); Return 'system error '; } $ DataSeek = implode ('', unpack ('L', $ DataSeek. chr (0 ))); Fseek ($ fd, $ DataSeek ); $ IpData2 = fread ($ fd, 4 ); If (strlen ($ ipData2) <4 ){ Fclose ($ fd ); Return 'system error '; } $ Ip2num = implode ('', unpack ('L', $ ipData2 )); If ($ ip2num <0) $ ip2num + = pow (2, 32 ); // Unknown prompt not found If ($ ip2num <$ ipNum ){ If ($ Middle = $ BeginNum ){ Fclose ($ fd ); Return 'unknown '; } $ BeginNum = $ Middle; } } // The following code is dizzy. if you do not understand it, read it slowly. $ IpFlag = fread ($ fd, 1 ); If ($ ipFlag = chr (1 )){ $ IpSeek = fread ($ fd, 3 ); If (strlen ($ ipSeek) <3 ){ Fclose ($ fd ); Return 'system error '; } $ IpSeek = implode ('', unpack ('L', $ ipSeek. chr (0 ))); Fseek ($ fd, $ ipSeek ); $ IpFlag = fread ($ fd, 1 ); } If ($ ipFlag = chr (2 )){ $ AddrSeek = fread ($ fd, 3 ); If (strlen ($ AddrSeek) <3 ){ Fclose ($ fd ); Return 'system error '; } $ IpFlag = fread ($ fd, 1 ); If ($ ipFlag = chr (2 )){ $ AddrSeek2 = fread ($ fd, 3 ); If (strlen ($ AddrSeek2) <3 ){ Fclose ($ fd ); Return 'system error '; } $ AddrSeek2 = implode ('', unpack ('L', $ AddrSeek2.chr (0 ))); Fseek ($ fd, $ AddrSeek2 ); } Else { Fseek ($ fd,-1, SEEK_CUR ); } While ($ char = fread ($ fd, 1 ))! = Chr (0 )) $ IpAddr2. = $ char; $ AddrSeek = implode ('', unpack ('L', $ AddrSeek. chr (0 ))); Fseek ($ fd, $ AddrSeek ); While ($ char = fread ($ fd, 1 ))! = Chr (0 )) $ IpAddr1. = $ char; } Else { Fseek ($ fd,-1, SEEK_CUR ); While ($ char = fread ($ fd, 1 ))! = Chr (0 )) $ IpAddr1. = $ char; $ IpFlag = fread ($ fd, 1 ); If ($ ipFlag = chr (2 )){ $ AddrSeek2 = fread ($ fd, 3 ); If (strlen ($ AddrSeek2) <3 ){ Fclose ($ fd ); Return 'system error '; } $ AddrSeek2 = implode ('', unpack ('L', $ AddrSeek2.chr (0 ))); Fseek ($ fd, $ AddrSeek2 ); } Else { Fseek ($ fd,-1, SEEK_CUR ); } While ($ char = fread ($ fd, 1 ))! = Chr (0 )){ $ IpAddr2. = $ char; } } Fclose ($ fd ); // Return the result after the replacement operation is completed. If (preg_match ('/http/I', $ ipAddr2 )){ $ IpAddr2 = ''; } $ Ipaddr = "$ ipAddr1 $ ipAddr2 "; $ Ipaddr = preg_replace ('/CZ88.Net/is', '', $ ipaddr ); $ Ipaddr = preg_replace ('/^ s */is', '', $ ipaddr ); $ Ipaddr = preg_replace ('/s * $/is', '', $ ipaddr ); If (preg_match ('/http/I', $ ipaddr) | $ ipaddr = ''){ $ Ipaddr = 'unknown '; } Return $ ipaddr; } Header ("Content-type: text/html; charset = utf-8 "); $ Ip = $ _ SERVER ['http _ X_FORWARDED_FOR ']; If (isset ($ _ GET ['Q']) { $ Ip = $ _ GET ['Q']; If (filter_var ("http: //". $ ip, FILTER_VALIDATE_URL, FILTER_FLAG_HOST_REQUIRED )){ $ Ip = gethostbyname ($ ip ); } } Echo "$ ip,". mb_convert_encoding (convertip ($ ip), "UTF-8", "gb2312 "); ?>