php 如何上传图片

<code class="html"><form action="upload.php" method="post" enctype="multipart/form-data">
  <input type="file" name="image" />
  <input type="submit" value="上传" />
</form></code>

<code class="php">if ($_FILES["image"]["error"] === UPLOAD_ERR_OK) {
  // 文件已成功上传
  $fileName = $_FILES["image"]["name"];
  $tmpName = $_FILES["image"]["tmp_name"];

  // 检查文件类型，只允许特定的类型（例如，图片）
  $allowedTypes = array("image/jpeg", "image/png", "image/gif");
  if (!in_array($_FILES["image"]["type"], $allowedTypes)) {
    echo "只允许上传图片文件！";
    exit;
  }

  // 将文件移动到永久存储位置
  $uploadDir = "uploads/";
  if (!file_exists($uploadDir)) {
    mkdir($uploadDir, 0755, true);
  }
  $destinationPath = $uploadDir . $fileName;
  if (move_uploaded_file($tmpName, $destinationPath)) {
    echo "图片上传成功！";
  } else {
    echo "图片上传失败！";
  }
} else {
  // 文件上传错误
  $errorMessage = "上传图片时出错：" . $_FILES["image"]["error"];
  echo $errorMessage;
}</code>