Example of php IP address regular expression-PHP source code

In php, there are user-defined functions that can help you determine the IP address, and we also use regular functions to determine the IP address. Below I will summarize some methods to verify the IP address. In php, there are user-defined functions that can help you determine the IP address, and we also use regular functions to determine the IP address. Below I will summarize some methods to verify the IP address.

Script ec (2); script

The filter function filters IP addresses by using the following methods:

The Code is as follows:
Echo filter_var ("127.0.0.1", "FILTER_VALIDATE_INT"); // return true or false

Example.

Determine whether the IP address is valid

The Code is as follows:
If (filter_var ($ ip, FILTER_VALIDATE_IP )){ // It's valid } Else { // It's not valid }

Check whether it is a legal public IPv4 address. Private IP addresses such as 192.168.1.1 will be excluded.

The Code is as follows:
If (filter_var ($ ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4 | FILTER_FLAG_NO_PRIV_RANGE )){ // It's valid } Else { // It's not valid }

Determine whether an IPv6 address is valid

The Code is as follows:
If (filter_var ($ ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_RES_RANGE )){ // It's valid } Else { // It's not valid }

Determine whether it is a public IPv4 IP address or a legal Public IPv6 IP Address

The Code is as follows:
If (filter_var ($ ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE )){ // It's valid } Else { // It's not valid }

Simple Regular Expressions

Preg_match ("/d {1, 3 }. d {1, 3 }. d {1, 3 }. d {1, 3}/"); // This method is not accurate. The maximum value is 255.255.255.255, but this is only the verification format. For example, 999.999.999.999 can also be verified.

Upgrade and Improvement

The Code is as follows:
Functionis_ip ($ gonten ){ $ Ip = explode (".", $ gonten ); For ($ I = 0; $ I { If ($ ip [$ I]> 255 ){ Return (0 ); } } Return ereg ("^ [0-9] {1, 3 }. [0-9] {1, 3 }. [0-9] {1, 3 }. [0-9] {1, 3} $ ", $ gonten ); }

This meets our requirements.

Next we will introduce a method to determine IP addresses:

The Code is as follows:

Function matchip ($ q ){ Preg_match ('/(25 [0-5]) | (2 [0-4] d) | (1dd) | ([1-9] d) | d) (. (25 [0-5]) | (2 [0-4] d) | (1dd) | ([1-9] d) | d )) {3}/', $ q, $ matches ); Return $ matches [0]; } $ Ipaddress = '1970. 103.2.2 '; $ Iperror = '2017. 3.6.6 '; $ Iptest = matchip ($ ipaddress ); // When the value of matchip is $ ipaddress, the output is 201.103.2.2. // When the value of the function given to matchip is $ iperror, the output value is 62.3.6.6 If ($ iptest) { Echo $ iptest; } Else { Echo 'www .111cn.net prompt: the IP address you entered is incorrect '; }