This time to everyone to bring PHP to determine the IP address of a valid IP addresses step by bit, PHP to determine the IP address of the effective IP addresses what, the following is the actual case, together to see.
Not also, after php5.2.0, there is a special function to do this judgment.
Determine if it is a legitimate IP
if (Filter_var ($ip, filter_validate_ip)) {//it ' s valid}else {//It's not valid}
Determine if the IPV4 IP address is valid
if (Filter_var ($ip, Filter_validate_ip, Filter_flag_ipv4)) {//it ' s valid}else {//It's not valid}
Determine if it is a valid public IPv4 address, 192.168.1.1 This type of private IP address will be excluded
if (Filter_var ($ip, filter_validate_ip, Filter_flag_ipv4 | Filter_flag_no_priv_range)) {//it ' s valid}else {//It's not valid}
Determine if the IPV6 address is valid
if (Filter_var ($ip, Filter_validate_ip, Filter_flag_no_res_range)) {//it ' s valid}else {//It's not valid}
Determines whether the public IPv4 IP or is a legitimate public IPv6 IP address
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}
Believe that you have read the case of this article you have mastered the method, more exciting please pay attention to the PHP Chinese network other related articles!
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