在php post方法中使用jquery

Question

我在jquery和ajax方面不是很有經驗，但我需要以下內容。用戶成功登錄後，他們可以從該頁面下載PDF文件。該網站有一個崩潰div，他們可以從中選擇要下載的文件。一切都在PHP中完成，並行得通。但是，如果找不到文件，摺疊div將被關閉。換句話說，網頁被重新加載。因此，用戶必須新作出新的選擇，這是不方便的。所以我會以下。如果找不到該文件，那麼div應該保持摺疊狀態，並在表單上的輸入字段's'中保留以前的值。我知道這應該通過jQuery或JavaScript來完成。我嘗試了以下，但它不起作用。

  //PHP 

    <?php 
    //if download is clicked 
    if (isset($_POST["download"])) { 
    $data = $_POST["s"]; 

    //if file is found 
    if (fileexists($data){ 
    // We'll be outputting a PDF 
    header('Content-type: application/pdf'); 

    // It will be called downloaded.pdf 
    header('Content-Disposition: attachment; filename="downloaded.pdf"'); 

    // The PDF source is in original.pdf 
    readfile($data); 
    } 
    //else the div should remain open 
    else{ 
     echo "<script> if ($('#collapseOne').is(':hidden')) { 
       $('#collapseOne').show(); 
       }</script>"; 
    } 
    } 
    ?>    

     <div id="collapseOne" class="panel-collapse collapse"> 
      <div class="panel-body"> 
       <form id='searchForm' method="post" action=''> 
       <p><label>Select Month</label></p> 
       <input id='s' name = 's' type='text' required><br><br> 
       <button type="submit" id='download' name='download' class='btn btn-default btn-lg'> 
        <span class='glyphicon glyphicon-download-alt'></span> Download 
       </button> 
       <br> <br> 
       <button id='download1' name = 'download1' class='btn btn-default btn-lg'> 
        <span class='glyphicon glyphicon-download-alt'></span> Download All 
       </button> 
       </form>    
       </div> 
     </div> 

Answer 1

總之，你呼應PHP到JavaScript

<script> 
    $(document).ready(function(){ 
     var hasDownload = "<?php echo $_POST['download']; ?>"; 
     var oldInput = "<?php echo $_POST['s']; ?>"; 
     if(hasDownload == false) { 
      $('#collapseOne').show(); 
      $('input#s').val(oldInput); 
     } 
    })   
</script> 

當服務器提供文件，這些值將出席你的Javascript。把你的jQuery放在另一個if語句的底部&這是一個doc準備好的塊，這樣dom首先被加載並且將你的PHP變量回顯成Javascript變量來執行你的jQuery邏輯。

<?php 

    if (isset($_POST["download"]) && fileexists($_POST["s"]) { 
     header('Content-type: application/pdf'); 
     header('Content-Disposition: attachment; filename="downloaded.pdf"'); 
     readfile($_POST["s"]); 

    } 

?>    

<div id="collapseOne" class="panel-collapse collapse"> 
    <div class="panel-body"> 
     <form id='searchForm' method="post" action=''> 
      <p><label>Select Month</label></p> 
      <input id='s' name = 's' type='text' required><br><br> 
      <button type="submit" id='download' name='download' class='btn btn-default btn-lg'> 
       <span class='glyphicon glyphicon-download-alt'></span> Download 
      </button> 
      <br> <br> 
      <button id='download1' name = 'download1' class='btn btn-default btn-lg'> 
       <span class='glyphicon glyphicon-download-alt'></span> Download All 
      </button> 
     </form>    
    </div> 
</div> 

<?php if(isset($_POST["download"]) == false && fileexists($_POST["s"] == false) : ?> 
    <script> 
     $(document).ready(function(){ 
      var hasDownload = "<?php echo $_POST['download']; ?>"; 
      var oldInput = "<?php echo $_POST['s']; ?>"; 
      if(hasDownload == false) { 
       $('#collapseOne').show(); 
       $('input#s').val(oldInput); 
      } 
     })   
    </script> 
<?php endif; ?> 

Answer 2

試試用這個吧！

$.ajax({ 
    url:"/path/to/your/script/", 
    type: "post", 
    data: //fetch the data which you want to pass 
}).done(function(status){ 
    //status is the data returned from the script called 
});