这是我的整个PHP代码，我收到错误

Question

<?php
$db_server_nm = "localhost:3306";
$db_user_name = "root";
$db_password = "root";
$db_name = "cacs";

 // create connection
$connection = mysqli_connect($db_server_nm, $db_user_name, $db_password, $db_name);

// checking connection

if ( ! $connection){
  die('Cannot be Connected :'.mysqli_connect_error($connection));
 }
 echo ("Connected to database<br>");

 /*
  $user_nm = $_POST['User Name'];
  $pwd = $_POST['Password'];

   echo ("User:- " .$db_user_name ." and PWD :-" .$db_password . "<br>");

 */ 

$sql_android_metadata =  "SELECT * FROM `android_metadata`";      
$sql_chapter = "SELECT * FROM `chapter`";
$sql_course = "SELECT * FROM `course`";
$sql_cpt_part1 = "SELECT * FROM `cpt_part1`";   
$sql_question = "SELECT * FROM `questions`";
$sql_exam = "SELECT * FROM `exam`";
$sql_exercie = "SELECT * FROM `exercise`";
$sql_paper =  "SELECT * FROM `paper`";
$sql_resultdisplay = "SELECT * FROM `resultdisplay`";
$sql_section = "SELECT * FROM `section`";
$sql_subject = "SELECT * FROM `subject`";
$sql_test_of_cpt = "SELECT * FROM `test_of_cpt`";
$sql_test_of_ipcc = "SELECT * FROM `test_of_ipcc`";

$res_am = mysqli_query($connection, $sql_android_metadata);
$row = mysqli_fetch_array($res_am);

$res_chap = mysqli_query($connection, $sql_chapter);
$row = mysqli_fetch_array($res_chap);

$res_course = mysqli_query($connection, $sql_course);
$row = mysqli_fetch_array($res_course);

$res_cpp1 = mysqli_query($connection, $sql_cpt_part1);
$row = mysqli_fetch_array($res_cpp1);

$res_ques = mysqli_query($connection, $sql_question);
$row = mysqli_fetch_array($res_ques);

$res_exer = mysqli_query($connection, $sql_exercie);
$row = mysqli_fetch_array($res_exer);

$res_paper = mysqli_query($connection, $sql_paper);
$row = mysqli_fetch_array($res_paper);

$res_resdisp = mysqli_query($connection, $sql_resultdisplay);
$row = mysqli_fetch_array($res_resdisp);

$res_sect = mysqli_query($connection, $sql_section);
$row = mysqli_fetch_array($res_sect);

$res_sub = mysqli_query($connection, $sql_subject);
$row = mysqli_fetch_array($res_sub);

$res_test_cpt = mysqli_query($connection, $sql_test_of_cpt);
$row = mysqli_fetch_array($res_test_cpt);

$res_test_ipcc= mysqli_query($connection, $sql_test_of_ipcc);
$row = mysqli_fetch_array($res_test_ipcc);

//$data=$row[0];

 if(! ($res_am || $res_chap || $res_course || $res_cpp1 || $res_ques ||   $res_exer || $res_paper 
    || $res_resdisp || $res_sect || $res_sub || $res_test_cpt || $test_of_ipcc)){
  die ('Data cannot be retrieved:'. mysqli_error($connection));  }    


  echo "<br> Data retrieved Successfully";

   $connection-> close();
 ?>

收到此错误...

1045 - 用户'root'@'@ localhost'拒绝访问（密码：是）

但是当我将mysqli_connect（）更改为新的msqli时，它可以工作。使用的方法或其他方面是否有任何问题。 请帮助我

Answer 1

PHP doc for msqli_connect/__construct表示端口应该是第5个参数。严格地说，这意味着第一个参数应该是localhost（而不是localhost:3306），第五个参数应该是3306）。也许msqli_connect强制执行此操作，而new则不执行此操作。值得一试。