窗體停止用戶已經

Question

登錄後，將數據傳遞我想在頁面上對項目進行排序，併爲我使用這種形式：形式已被處理

<form method="get" action=""> 
      <label for="sort">Sort items by</label> 
      <select id="sort" name="sort"> 
       <option value="">-</option> 
       <option value="plth">Price (Low to high)</option> 
       <option value="phtl">Price (High to low)</option> 
       <option value="naz">Name (A-Z)</option> 
       <option value="nza">Name (Z-A)</option> 
      </select> 
      <input type="submit" name="sortSubmit" value="GO >"> 
     </form> 

後，我會用一些SQL語句從數據庫中檢索所需順序中的項目：

if(isset($_GET["sortSubmit"]) && $_GET["sort"] == "plth") { 
        $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY PRICE ASC"; 
       } 
       elseif (isset($_GET["sortSubmit"]) && $_GET["sort"] == "phtl") { 
        $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY PRICE DESC"; 
       } 
       elseif (isset($_GET["sortSubmit"]) && $_GET["sort"] == "naz") { 
        $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY NAME ASC"; 
       } 
       elseif (isset($_GET["sortSubmit"]) && $_GET["sort"] == "nza") { 
        $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY NAME DESC"; 
       } 

的問題是，一切工作正常，直到一個用戶登錄的用戶登錄後，它停止工作完全和我想不通爲什麼。通過一些測試回聲聲明，我發現表單不再傳遞任何數據。我無法想象這是如何做會議或cookie的東西。 感謝您的任何想法。

Answer 1

<form method="get" action=""> 
    <label for="sort">Sort items by</label> 
    <select id="sort" name="sort"> 
     <option value="">-</option> 
     <option value="plth">Price (Low to high)</option> 
     <option value="phtl">Price (High to low)</option> 
     <option value="naz">Name (A-Z)</option> 
     <option value="nza">Name (Z-A)</option> 
    </select> 
    <input type="submit" value="go"> 
    </form> 

現在，如果這個頁面被稱爲sort.php te表單也會提交給sort.php。

這樣，在標題中你可以讀取像這樣的值。

$sort = $_GET['sort']; 
switch ($sort){ 
case "plth": 
$retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY PRICE ASC"; 
break; 
// Other possible value andling here 

Answer 2

... 
The ordered data 
... 
<form method="get" action="index.php"> 
    <input type hidden name="manager_action" value="sort"> 
      <label for="sort">Sort items by</label> 
      <select id="sort" name="sort"> 
       <option value="">-</option> 
       <option value="plth">Price (Low to high)</option> 
       <option value="phtl">Price (High to low)</option> 
       <option value="naz">Name (A-Z)</option> 
       <option value="nza">Name (Z-A)</option> 
      </select> 
</form> 

<?php // index.php 
... 
if($_POST['manager_action']=='sort'){ 
    // regenerate data in right ordered 
    // and again generate the html page 
} 
... 

?> 

Answer 3

<form method="get" action=""> 
    <label for="sort">Sort items by</label> 
    <select id="sort" name="sort"> 
     <option value="">-</option> 
     <option value="plth">Price (Low to high)</option> 
     <option value="phtl">Price (High to low)</option> 
     <option value="naz">Name (A-Z)</option> 
     <option value="nza">Name (Z-A)</option> 
    </select> 

    <input type="submit" name="sortSubmit" value="go"> 
</form> 

注意被交換出去。這將提交表單並告訴它添加www.yourwebsite.com?sort=nza（例如）

然後在您的PHP中，您可以正確使用if/else或創建switch語句。我將使用switch語句，因爲它比一堆if/else更快一些。

<?php 
    if(isset($_GET["sortSubmit"])) { // Ask whether the form was submitted or not. Not technically required though. 
     switch($_GET["sort"]) { 
      case "plth": 
       $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY PRICE ASC"; 
       break; 
      case "phtl": 
       $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY PRICE DESC"; 
       break; 
      case "naz": 
       $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY NAME ASC"; 
       break; 
      case "nza": 
       $retrieve = "SELECT * FROM products WHERE ID <= '9' ORDER BY NAME DESC"; 
       break; 
      default: 
       // Catch anything else 
       break; 
     } 
    } 
?>