php - 如何通过Ajax发送php变量仅当它不为空时

Question

所以我有 4 个名为 $description,$hscode,$from,$to 的 php 变量，我想通过 AJAX 请求发送这些变量。我不完整的尝试是这样的:

function searchFilter(page_num) {
  page_num = page_num?page_num:0;

    $.ajax({
        type: 'POST',
        url: 'getData.php',
       data: { page : +page_num, "desc" : "<?php  print $description ?>","hscode" : "<?php  print $hscode ?>","from" : "<?php  print $from ?>","to" : "<?php $to ?>" },

        beforeSend: function () {
            $('.container-fluid').waitMe({
                   effect : 'stretch',
                   bg : 'rgba(255,255,255,0.7)'
                });
             },
        success: function (html) {
            $('#posts_content').html(html);
            $('.container-fluid').waitMe("hide");
        }
    });
}

问题是，PHP 变量是动态的，意味着它们并不总是被设置，有时仅设置 $description，有时仅设置 $hscode，有时 $ description 和 $hscode 仅设置，此类型有 6 种组合。请帮助在这种情况下我该如何发送此请求。

POSSIBLE Answer:

代码工作正常，但我很困惑这是正确的方法吗，如果我错了，请纠正我，我的工作代码是:

function searchFilter(page_num) {
  page_num = page_num?page_num:0;

    $.ajax({
        type: 'POST',
        url: 'getData.php',
        data :  { page : +page_num, 
                  <?php if(isset($description)){ echo '"desc"'.' : '. "'$description'" . ',';} ?>
                  <?php if(isset($hscode)){ echo '"hscode"'.' : '. "'$hscode'" . ',';} ?>
                  <?php if(isset($from)){ echo '"from"'.' : '. "'$from'" . ',';} ?>
                  <?php if(isset($to)){ echo '"to"'.' : '. "'$to'" . ',';} ?> },


        beforeSend: function () {
            $('.container-fluid').waitMe({
                   effect : 'stretch',
                   bg : 'rgba(255,255,255,0.7)'
                });
             },
        success: function (html) {
            $('#posts_content').html(html);
            $('.container-fluid').waitMe("hide");
        }
    });
}

Answer 1

首先，您可以检查变量是否已设置，如果已设置，则将这些变量附加到ajax数据中。尝试以下代码:

function searchFilter(page_num) {
    page_num = page_num?page_num:0;
    send_data = {};
    send_data.page = +page_num;
    <?php if (isset($description)): ?>
    send_data.desc = "<?php echo $description ?>";
    <?php endif; ?>
    <?php if (isset($hscode)): ?>
    send_data.hscode = "<?php echo $hscode ?>";
    <?php endif; ?>
    <?php if (isset($from)): ?>
    send_data.from = "<?php echo $from ?>";
    <?php endif; ?>
<?php if (isset($to)): ?>
send_data.to = "<?php echo $to ?>";
<?php endif; ?>

      $.ajax({
          type: 'POST',
          url: 'getData.php',
         data: send_data,

          beforeSend: function () {
              $('.container-fluid').waitMe({
                     effect : 'stretch',
                     bg : 'rgba(255,255,255,0.7)'
                  });
               },
          success: function (html) {
              $('#posts_content').html(html);
              $('.container-fluid').waitMe("hide");
          }
      });
}