我试图将我的 mysql 更改为 mysqli。当我这样做时，我得到了错误。我尝试了一切，但我没有找到解决方案。
我遇到的错误：（你看到的并不是所有的错误）
警告：mysqli_query() 期望参数 1 为 mysqli，
在第 219 行的 C:\xampp\htdocs\follow\include\database.php 中给出 null警告：mysqli_num_rows() 期望参数 1 为 mysqli_result，在第 220 行的 C:\xampp\htdocs\follow\include\database.php 中给出 null
警告：mysqli_query() 期望参数 1 为 mysqli，在第 231 行的 C:\xampp\htdocs\follow\include\database.php 中给出 null
警告：mysqli_num_rows() 期望参数 1 为 mysqli_result，在第 232 行的 C:\xampp\htdocs\follow\include\database.php 中给出 null
警告：mysqli_query() 期望参数 1 为 mysqli，在第 102 行的 C:\xampp\htdocs\follow\include\database.php 中给出 null
...更多错误
这是我的 php 代码
<?php
/**
* Please subscribe to our feeds at http://blog.geotitles.com for more such tutorials
*/
include("constants.php");
class MySQLDB
{
var $connection; //The MySQL database connection
var $num_active_users; //Number of active users viewing site
var $num_active_guests; //Number of active guests viewing site
var $num_members; //Number of signed-up users
/* Note: call getNumMembers() to access $num_members! */
/* Class constructor */
function MySQLDB(){
/* Make connection to database */
$con = mysqli_connect(DB_SERVER, DB_USER, DB_PASS,DB_NAME);
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
/**
* Only query database to find out number of members
* when getNumMembers() is called for the first time,
* until then, default value set.
*/
$this->num_members = -1;
if(TRACK_VISITORS){
/* Calculate number of users at site */
$this->calcNumActiveUsers();
/* Calculate number of guests at site */
$this->calcNumActiveGuests();
}
}
function confirmUserPass($username, $password){
GLOBAL $con;
/* Add slashes if necessary (for query) */
if(!get_magic_quotes_gpc()) {
$username = addslashes($username);
}
/* Verify that user is in database */
$q = "SELECT password FROM ".TBL_USERS." WHERE username = '$username'";
$result = mysqli_query($con,$q);
if(!$result || (mysqli_num_rows($result) < 1)){
return 1; //Indicates username failure
}
/* Retrieve password from result, strip slashes */
$dbarray = mysqli_fetch_array($result);
$dbarray['password'] = stripslashes($dbarray['password']);
$password = stripslashes($password);
/* Validate that password is correct */
if($password == $dbarray['password']){
return 0; //Success! Username and password confirmed
}
else{
return 2; //Indicates password failure
}
}
function confirmUserID($username, $userid){
GLOBAL $con;
/* Add slashes if necessary (for query) */
if(!get_magic_quotes_gpc()) {
$username = addslashes($username);
}
/* Verify that user is in database */
$q = "SELECT userid FROM ".TBL_USERS." WHERE username = '$username'";
$result = mysqli_query($con,$q);
if(!$result || (mysqli_num_rows($result) < 1)){
return 1; //Indicates username failure
}
/* Retrieve userid from result, strip slashes */
$dbarray = mysqli_fetch_array($result);
$dbarray['userid'] = stripslashes($dbarray['userid']);
$userid = stripslashes($userid);
/* Validate that userid is correct */
if($userid == $dbarray['userid']){
return 0; //Success! Username and userid confirmed
}
else{
return 2; //Indicates userid invalid
}
}
function usernameTaken($username){
GLOBAL $con;
if(!get_magic_quotes_gpc()){
$username = addslashes($username);
}
$q = "SELECT username FROM ".TBL_USERS." WHERE username = '$username'";
$result = mysqli_query($con,$q);
return (mysqli_numrows($result) > 0);
}
function usernameBanned($username){
GLOBAL $con;
if(!get_magic_quotes_gpc()){
$username = addslashes($username);
}
$q = "SELECT username FROM ".TBL_BANNED_USERS." WHERE username = '$username'";
$result = mysqli_query($con,$q);
return (mysqli_numrows($result) > 0);
}
function addNewUser($username, $password, $email){
GLOBAL $con;
$time = time();
/* If admin sign up, give admin user level */
if(strcasecmp($username, ADMIN_NAME) == 0){
$ulevel = ADMIN_LEVEL;
}else{
$ulevel = USER_LEVEL;
}
$q = "INSERT INTO ".TBL_USERS." VALUES ('$username', '$password', '0', $ulevel, '$email', $time)";
return mysqli_query($con,$q);
}
function updateUserField($username, $field, $value){
$q = "UPDATE ".TBL_USERS." SET ".$field." = '$value' WHERE username = '$username'";
return mysqli_query($con,$q);
}
function getUserInfo($username){
GLOBAL $con;
$q = "SELECT * FROM ".TBL_USERS." WHERE username = '$username'";
$result = mysqli_query($con,$q);
/* Error occurred, return given name by default */
if(!$result || (mysqli_num_rows($result) < 1)){
return NULL;
}
/* Return result array */
$dbarray = mysqli_fetch_array($result);
return $dbarray;
}
function getNumMembers(){
GLOBAL $con;
if($this->num_members < 0){
$q = "SELECT * FROM ".TBL_USERS;
$result = mysqli_query($con,$q);
$this->num_members = mysqli_num_rows($result);
}
return $this->num_members;
}
/**
* calcNumActiveUsers - Finds out how many active users
* are viewing site and sets class variable accordingly.
*/
function calcNumActiveUsers(){
GLOBAL $con;
/* Calculate number of users at site */
$result = mysqli_query($con,"SELECT * FROM ".TBL_ACTIVE_USERS);
$this->num_active_users = mysqli_num_rows($result);
}
function calcNumActiveGuests(){
GLOBAL $con;
/* Calculate number of guests at site */
$q = "SELECT * FROM ".TBL_ACTIVE_GUESTS;
$result = mysqli_query($con,$q);
$this->num_active_guests = mysqli_num_rows($result);
}
function addActiveUser($username, $time){
GLOBAL $con;
$q = "UPDATE ".TBL_USERS." SET timestamp = '$time' WHERE username = '$username'";
mysqli_query($con,$q);
if(!TRACK_VISITORS) return;
$q = "REPLACE INTO ".TBL_ACTIVE_USERS." VALUES ('$username', '$time')";
mysqli_query($con,$q);
$this->calcNumActiveUsers();
}
function addActiveGuest($ip, $time){
GLOBAL $con;
if(!TRACK_VISITORS) return;
$q = "REPLACE INTO ".TBL_ACTIVE_GUESTS." VALUES ('$ip', '$time')";
mysqli_query($con,$q);
$this->calcNumActiveGuests();
}
function removeActiveUser($username){
GLOBAL $con;
if(!TRACK_VISITORS) return;
$q = "DELETE FROM ".TBL_ACTIVE_USERS." WHERE username = '$username'";
mysqli_query($con,$q);
$this->calcNumActiveUsers();
}
/* removeActiveGuest */
function removeActiveGuest($ip){
GLOBAL $con;
if(!TRACK_VISITORS) return;
$q = "DELETE FROM ".TBL_ACTIVE_GUESTS." WHERE ip = '$ip'";
mysqli_query($con,$q);
$this->calcNumActiveGuests();
}
/* removeInactiveUsers */
function removeInactiveUsers(){
GLOBAL $con;
if(!TRACK_VISITORS) return;
$timeout = time()-USER_TIMEOUT*60;
$q = "DELETE FROM ".TBL_ACTIVE_USERS." WHERE timestamp < $timeout";
mysqli_query($con,$q);
$this->calcNumActiveUsers();
}
/* removeInactiveGuests */
function removeInactiveGuests(){
GLOBAL $con;
if(!TRACK_VISITORS) return;
$timeout = time()-GUEST_TIMEOUT*60;
$q = "DELETE FROM ".TBL_ACTIVE_GUESTS." WHERE timestamp < $timeout";
mysqli_query($con,$q);
$this->calcNumActiveGuests();
}
function query($query){
GLOBAL $con;
return mysqli_query($con,$query);
}
};
$database = new MySQLDB;
?>