method to determine whether an IP address is within a specified range

For example, given an IP segment: 127.0.0.1 ~ 127.0.0.255, we want to determine whether a given IP address is in this section, you can first convert the IP address to an integer, and then the integer comparison size is very easy.

For example:
127.0.0.1 = 2130706433
127.0.0.255 = 2130706687

Judge:
127.0.1.253 = 2130706941
Whether the integer size is directly compared within this range can be

To convert an IP address into an integer:

 Public Static LongIp2long (stringIP) {  string[] ipbytes; Doublenum =0; if(!string. IsNullOrEmpty (IP)) {ipbytes= IP. Split ('.');  for(inti = ipbytes.length-1; I >=0; i--) {num+= ((int. Parse (Ipbytes[i])% the) * MATH.POW ( the, (3-i))); }  }  return(Longnum;}

Determines whether a given IP address is within the specified range:

long start = IP2Long( "127.0.0.1" ); long end = IP2Long( "127.0.0.255" ); long ipAddress = IP2Long( "127.0.1.253" ); bool inRange = (ipAddress >= start && ipAddress <= end); if (inRange){   //IP Address fits within range! }

method to determine whether an IP address is within a specified range