无法使用PHP获取MySql输出

Question

我是PHP和MySql的新手。我正在尝试连接到MySql数据库并在屏幕上显示其内容。但没有显示出来。虽然我能够获得“祝贺”的信息，但我无法获得任何其他信息。请帮我弄清楚我的代码有什么问题。

<?php 
    $dbhost= "localhost"; 
    $dbuser= "root"; 
    $dbpass= ""; 
    $dbconnect= mysqli_connect('$dbhost', '$dbuser', '$dbpass','$mydb'); 
    /*mysqli_select_db($mydb);*/ 
     if(!mysqli_select_db){ 
      echo "database not found"; 
      die(mysqli_error()); 
     } 
     else{ 
      echo "congrats"; 
     } 


    $query = "SELECT * FROM userinfo"; 
    $result = mysqli_query($dbconnect, $query); 

    while($record = mysqli_fetch_array($result)){ 
     echo $record['Name'], $record['Email'], $record['Contact']; 
    } 

?> 

Answer 1

您尚未定义$mydb变量的值。也做了其他几个更正。尝试执行下面的代码。

<?php 
    $dbhost= "localhost"; 
    $dbuser= "root"; 
    $dbpass= ""; 
    $mydb = "your_dbname"; 
    $dbconnect= mysqli_connect($dbhost, $dbuser, $dbpass,$mydb); 
    /*mysqli_select_db($mydb);*/ 
     if(!mysqli_select_db){ 
      echo "database not found"; 
      die(mysqli_error()); 
     } 
     else{ 
      echo "congrats"; 
     } 


    $query = "SELECT * FROM userinfo"; 
    $result = mysqli_query($dbconnect, $query); 

    while($record = mysqli_fetch_array($result)){ 
     echo $record['Name']." ".$record['Email']." ".$record['Contact']; 
    } 

?>