Question

我已经成功启动了Apache，但在我写了一个简单的login.html和login.php之后，我发现我在Mysql数据库中获取了数据。

没有运行时错误，但我使用$result=$conn->query($sql);获得的对象始终为NULL;

操作系统：Windows 8.1 Wampserver latest version

的login.php

<?php
   session_start();
   $conn = new mysqli('localhost', 'root', '' , 'mylogin');
  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }

  $sql = "SELECT * FROM logintable";
  $result=$conn->query($sql);

  echo "\n".var_dump($result)."\n";
  //The problem is the query can't any data, so I delete the following code.
?>

的login.html

<!DOCTYPE html>
  <html>
  <head>
    <meta charset="utf-8">
     <script language="javascript"type="text/javascript" >
         function check(){
             var name=LoginForm.username.value;
             var pwd=LoginForm.password.value;
             if(name==""){
                  alert("Enter Username");
                  LoginForm.username.focus();
                  return (false);
             }
             if(pwd==""){
                  alert("Enter Password");
                  LoginForm.password.focus();
                  return (false);
             }
         }
     </script>
  </head>
  <body>
     <div class="center">
         <form name="LoginForm" method="post" action="login.php" onsubmit="return check(this)">
             username:<input name="username" type="text"id="username"/><br />
             password:<input name="password" type="password"id="password"/><br/>
             <input value="Login" type="submit" name="submit"/>
             <input value="register" type="button"onclick="javascrtpt:window.location.href='register.html'"/>
             <br/>
         </form>
     </div>
  </body>
  </html>

总是打印回声：

object(mysqli_result)[2]
  public 'current_field' => null
  public 'field_count' => null
  public 'lengths' => null
  public 'num_rows' => null
  public 'type' => null

Answer 1

现在我可以用这种方式获取数据：

<?php
   session_start();
   $conn = new mysqli('localhost', 'root', '' , 'mylogin');
  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }
  $sql = "SELECT * FROM logintable";

  if($result=$conn->query($sql))
  {
      echo "\n".var_dump($result)."\n";

      $row = $result->fetch_row();
      echo "\n".var_dump($row)."\n";
  } 
?>

$result是什么？

WampServer-＆gt; Mysql无法获取数据（始终返回NULL）

1 个答案: