循環mysqli更新，變量在while循環中增加1

Question

我正在嘗試循環此代碼，因為它將動態生成。 它從 mysql 獲取行數並循環多次。 POST 來自 ajax，它也在那里循環並且運行良好。 在 php 部分，我不確定為什么它不起作用。 我嘗試了很多不同的循環變化。

$queryEle = "SELECT * FROM featureSheetContent WHERE `user_id` = '$userID' AND `feature_id` = '$featureID'";
  $resultEle = mysqli_query($connect,$queryEle);
  $rowEle = mysqli_num_rows($resultEle);

  $i = 1;

  while ($i < $rowEle) {
    $eleID.$i = $_POST['eleID'.$i];
    $eleID .= $eleID.$i;
    $resizeWidth.$i = $_POST['resizeWidth'.$i];
    $resizeWidth .= $eleID.$i;
    $resizeHeight.$i = $_POST['resizeHeight'.$i];
    $resizeHeight .= $eleID.$i;

    $UploadMain = $connect->prepare("UPDATE featureSheetContent SET `ele_width` = ?, `ele_height` = ? WHERE id = ?");
    $UploadMain->bind_param('sss', $resizeWidth, $resizeHeight, $eleID);
    $UploadMain->execute();

    $i++;
  }

未循環代碼有效：

  $eleID1 = $_POST['eleID1'];
  $resizeWidth1 = $_POST['resizeWidth1'];
  $resizeHeight1 = $_POST['resizeHeight1'];
  $eleID2 = $_POST['eleID2'];
  $resizeWidth2 = $_POST['resizeWidth2'];
  $resizeHeight2 = $_POST['resizeHeight2'];

  
  $UploadMain = $connect->prepare("UPDATE featureSheetContent SET `ele_width` = ?, `ele_height` = ? WHERE id = ?");
  $UploadMain->bind_param('sss', $resizeWidth1, $resizeHeight1, $eleID1);
  $UploadMain->execute();
  $UploadMain = $connect->prepare("UPDATE featureSheetContent SET `ele_width` = ?, `ele_height` = ? WHERE id = ?");
  $UploadMain->bind_param('sss', $resizeWidth2, $resizeHeight2, $eleID2);
  $UploadMain->execute();

Answer 1

您的變量變量語法錯誤； 正確的語法是${"eleID".$i} 。 但是沒有必要在循環中每次都使用不同的變量。 將UPDATE查詢綁定到一組特定的變量，並從POST變量中重新分配這些變量。

$eleID = $resizeWidth = $resizeHeight = null; // Create the variables before binding
$UploadMain = $connect->prepare("UPDATE featureSheetContent SET `ele_width` = ?, `ele_height` = ? WHERE id = ?");
$UploadMain->bind_param('sss', $resizeWidth, $resizeHeight, $eleID);

for ($i = 1; $i <= $rowEle; $i++) {
    $eleID = $_POST['eleID'.$i];
    $resizeWidth = $_POST['resizeWidth'.$i];
    $resizeHeight = $_POST['resizeHeight'.$i];
    $UploadMain->execute();
}

順便說一句，您的UPDATE查詢將為任何用戶更新一行，而不僅僅是user_id = '$userID' 。 這是故意的嗎？