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I wrote several functions related to ID cards, which I personally find quite useful. Especially when conducting online questionnaire surveys, it is very useful to verify ID cards in personal information. However, there were only a few applicants, so I still included them in Forget it in your own blog. // Weighting factor $checksum = 0; $mod = $checksum % 11; return $verify_number; } // Upgrade the 15-digit ID card to 18-digits //18-digit ID card verification code validity check if (strlen($idcard) != 18){ return false; } if (idcard_verify_number($idcard_base) != strtoupper(substr($idcard, 17, 1))){ }
// Calculate ID card verification code according to national standard GB 11643-1999
function idcard_verify_number($idcard_base){
if (strlen($idcard_base) != 17) { return false; }
$factor = array(7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2);
// Verification code corresponding value
$verify_number_list = array(1, 0, X, 9, 8, 7, 6, 5, 4, 3, 2);
for ($i = 0; $i < strlen($idcard_base); $i++){
$checksum += substr($idcard_base, $i, 1) * $factor[$i];
}
$verify_number = $verify_number_list[$mod];
function idcard_15to18($idcard){
if (strlen($idcard) != 15){
return false;
}else {
// If the ID card sequence code is 996 997 998 999, these are special codes for people over 100 years old
if (array_search(substr($idcard, 12, 3), array(996, 997, 998, 999)) !== false){
$idcard = substr($idcard, 0, 6) . 18. substr($idcard, 6, 9); = substr($idcard, 0, 6) . 19. substr($idcard, 6, 9);
$idcard = $idcard . idcard_verify_number($idcard);
return $idcard;
}
$idcard_base = substr($idcard, 0, 17);
return false;
}else{
return true;
?>
The $idcard_base refers to the base code in the ID card. The base code is only found in the 18-digit ID card, which is the first 17 digits of the 18-digit ID card. The last digit is called the check code
Generally, you do not need to call idcard_verify_number() directly when using it. Most of the usual applications use the last two functions
These functions do not care about the format of the ID string. You must perform the format check before calling