Question

我正在研究我的学期项目，我想在下一页（order.php）中传递变量“ value”。它是从基于数据库填充的另一个下拉框的下拉框检索的值。我已经确认该值已存储，但无法在下一页检索它。

我尝试了localstorage（转NULL），会话变量（未定义的索引“值”）并将其放入url，但似乎没有任何效果，并且非常令人沮丧。有人可以帮我举个例子吗？谢谢

session_start();

$conn = new mysqli("localhost", "root", "", "restaurant_ordering");
mysqli_set_charset($conn,"utf8mb4");
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
} 
$sql = "select * from sector ";
$result = $conn->query($sql);



  while($row = $result->fetch_assoc()){
    $categories[] = array("id" => $row['id'], "val" => $row['name']);
  }

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

  while($row = $result->fetch_assoc()){
    $subcats[$row['sector_id']][] = array("id" => $row['id'], "val" => $row['name']);
  }

  $jsonCats = json_encode($categories);
  $jsonSubCats = json_encode($subcats);


?>

<!doctype html>
<html>

  <head>
    <script type='text/javascript'>
      <?php
        echo "var categories = $jsonCats; \n";
        echo "var subcats = $jsonSubCats; \n";
      ?>
      function loadCategories(){
        var select = document.getElementById("categoriesSelect");
        select.onchange = updateSubCats;
        for(var i = 0; i < categories.length; i++){
          select.options[i] = new Option(categories[i].val,categories[i].id);          
        }
      }
      function updateSubCats(){
        var catSelect = this;
        var catid = this.value;
        var subcatSelect = document.getElementById("subcatsSelect");
        subcatSelect.options.length = 0; 
        for(var i = 0; i < subcats[catid].length; i++){
          subcatSelect.options[i] = new Option(subcats[catid][i].val,subcats[catid][i].id);
        }
      }



    function handleSelectChange(event) {

    var selectElement = event.target;
    var value = selectElement.value;

}



    </script>
<meta charset="utf-8">
<title>New Order</title>
<link rel="stylesheet" href="server.css" />
  </head>

  <body onload='loadCategories()'>

  <p><a href="server.html"style="color:#ffcc00">Home</a> 


| <a href="../login.html"style="color:#ffcc00">Logout</a></p>
    <h2>New Order</h2>
<strong>Sector:</strong>

    <form name="form" method="post" action="order.php" >
    <select id='categoriesSelect'>
    </select>

    <select  id='subcatsSelect' onchange="handleSelectChange(event)">
    </select>



    <input type="hidden" name="new" value="1" />
<input type="hidden" name="select" id="total" value="">




</div>
</div>




<div id="button">
<p><input name="submit" type="submit" value="Submit" onclick= </p>
</div>

    </form>
  </body>
</html>```

Answer 1

已提交表单中的表单值将在“ order.php”中的$_POST变量中提供。通过使用想要输入值的表单输入的HTML“名称”属性来查找值。因此，如果您想要隐藏的“新”表单元素的值，请使用$_POST['new']在“ order.php”中获取值。

Answer 2

好吧，如果我知道您想从第一个php页面获取价值并传递到另一个php页面。因此，只需在第一个PHP中完成做

$ _ SESSION ['神话'] = $ value_that_want_pass;

在第二个php页面上做

session_start（）;

echo $ _SESSION ['mything'];

在php页面之间传递javascript值

2 个答案: