PHP authentication functions_PHP tutorial

Copy code The code is as follows:

// Calculate the ID card verification code according to the national standard GB 11643-1999
function idcard_verify_number($idcard_base){
if (strlen($idcard_base) != 17){ return false; }
// Weighting factor
$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');
$checksum = 0;
for ($i = 0; $i < strlen($idcard_base); $i++){
$checksum += substr($idcard_base, $i, 1) * $factor[$i];
}
$mod = $checksum % 11;
$verify_number = $verify_number_list[$mod];
return $verify_number;
}
// Upgrade the 15-digit ID card to 18 Bit
function idcard_15to18($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);
}else{
$idcard = substr( $idcard, 0, 6) . '19'. substr($idcard, 6, 9);
}
}
$idcard = $idcard . idcard_verify_number($idcard);
return $ idcard;
}
//18-digit ID card verification code validity check
function idcard_checksum18($idcard){
if (strlen($idcard) != 18){ return false; }
$idcard_base = substr($idcard, 0, 17);
if (idcard_verify_number($idcard_base) != strtoupper(substr($idcard, 17, 1))){
return false;
}else{
return true;
}
}
?>

The $idcard_base refers to the standard code in the ID card, and the standard code is the 18-digit ID card It is only found in , that is, the first 17 digits of the 18-digit ID card, and the last digit is called the verification code
Generally, you do not need to call idcard_verify_number() directly when using it. Most of the usual applications use the latter two functions
None of these functions care about the format of the ID string, and they perform format checks before calling

http://www.bkjia.com/PHPjc/320587.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/320587.htmlTechArticleCopy the code code as follows: ?php // Calculate the ID card verification code, according to the national standard GB 11643-1999 function idcard_verify_number($idcard_base){ if (strlen($idcard_base) != 17){ return f...