运行localhost时php中出错

Question

Following error in php while running through localhost

Warning: mysqli_select_db() expects parameter 1 to be mysqli, string given in C:\xampp\htdocs\IVPORTAL\admin\include\database.php on line 9

Warning: mysqli_error() expects exactly 1 parameter, 0 given in C:\xampp\htdocs\IVPORTAL\admin\include\database.php on line 9

i didn't get the error.

<?php 
require_once("config.php");

class database { 
    private $link;

    function __construct() {
        $this->link = mysqli_connect(config::host,config::username,config::passwor‌​d);
        mysqli_select_db(config::database,$this->link) or die(mysqli_error()); 
    } 

    function __distruct() {
        mysqli_close($this->link);
    } 

Answer 1

from the error it looks like you have missing params for function mysqli_error

following is syntax to use mysqli_error

mysqli_error(connection);

//change it to following
mysqli_error($this->link)

for the reference i have update your code

require_once("config.php"); 
class database { 
    private $link; 

    function __construct() {
        $this->link = mysqli_connect(config::host,config::username,config::passwor‌​d); 
        mysqli_select_db(config::database,$this->link) or die(mysqli_error($this->link)); 
    } 

    function __distruct() { 
        mysqli_close($this->link); 
}

it should work