Question

这是代码。由于某种原因，我无法找出它为什么不起作用正如你所看到的，我已经添加了一个测试查询，看看它是否会影响我的数据库上的任何更改，但是没有:(
有趣的是，在另一个PHP脚本中，我已成功连接数据库，甚至通过php脚本添加了一些记录。无法找到问题，谢谢提前 BTW。正如你所看到的，我已经将var“month”定义为字符串“hey”并在php脚本的末尾回显它以查看它是否发生了变化。但没有任何事情发生!!

  <form action="" name="form" id="form">
      <label>
          Select the month which you want to display its days.
          <select name="month" form="form" required>
            <option value="january">January</option>
            <option value="february">February</option>
            <option value="march">March</option>
            <option value="april">April</option>
            <option value="may">May</option>
            <option value="june">June</option>
            <option value="july">July</option>
            <option value="august">August</option>
            <option value="september">September</option>
            <option value="october">October</option>
            <option value="november">November</option>
            <option value="december">December</option>
          </select>
      </label>
      <input type="submit" name="update" value="Display" />
  </form>
  <?php
  $month = "hey";
  if(isset($_POST["update"]))
  {
      $month = $_POST["month"];
      $query = "SELECT * FROM `days` WHERE `month`='{$month}';";
      $conn = mysqli_connect("localhost","root","","db123");
      $result = mysqli_query($conn,$query);
      mysqli_query($conn,"INSERT INTO `days`(`month`,`day`) VALUES ('test','10');");
      if($result)
      {
          die("Sorry!");
      }
      while($row = mysqli_fetch_row($result))
      {
          echo $month;
          print_r($row);
      }
      mysqli_close($conn);
      echo $month;
  }

     ?

Answer 1

您没有指定方法，默认情况下为GET。更改此行

 if(isset($_POST["update"]))

到这个

 if(isset($_GET["update"]))

。或者，如果要将方法用作POST，则只需将方法指定为POST即可使用下面的代码

 <form action="" name="form" id="form" method="POST">
      <label>
          Select the month which you want to display its days.
          <select name="month" form="form" required>
            <option value="january">January</option>
            <option value="february">February</option>
            <option value="march">March</option>
            <option value="april">April</option>
            <option value="may">May</option>
            <option value="june">June</option>
            <option value="july">July</option>
            <option value="august">August</option>
            <option value="september">September</option>
            <option value="october">October</option>
            <option value="november">November</option>
            <option value="december">December</option>
          </select>
      </label>
      <input type="submit" name="update" value="Display" />
  </form>
  <?php
  $month = "hey";
  if(isset($_POST["update"]))
  {
      $month = $_POST["month"];
      $query = "SELECT * FROM `days` WHERE `month`='{$month}';";
      $conn = mysqli_connect("localhost","root","","db123");
      $result = mysqli_query($conn,$query);
      mysqli_query($conn,"INSERT INTO `days`(`month`,`day`) VALUES ('test','10');");
      if($result)
      {
          die("Sorry!");
      }
      while($row = mysqli_fetch_row($result))
      {
          echo $month;
          print_r($row);
      }
      mysqli_close($conn);
      echo $month;
  }

     ?>

希望这有助于你

Answer 2

 <?php
  $mysqli = new mysqli("localhost", "root", "", "db123");
 if ($mysqli->connect_errno) {
 echo "Failed to connect to MySQL: (" . $mysqli->connect_errno . ") " . $mysqli->connect_error;
  }
 $month = "hey";
 if(isset($_POST["update"]))
  {
  $month = $_POST["month"];
  $res = $mysqli->query("SELECT * FROM `days` WHERE `month`='{$month}'");
  mysqli_query($conn,"INSERT INTO `days`(`month`,`day`) VALUES ('test','10');");
  while($row = $res->num_rows)
  {
      echo $month;
      print_r($row);
  }
  mysqli_close($conn);
  echo $month;
 }
?>

php脚本无法连接MySQL

2 个答案: