通过php curl下载文件时显示文件大小

$url = "http://example.com/file.zip";
$file_path = "/path/to/save/file.zip";

// 初始化curl会话
$ch = curl_init($url);

// 设置选项
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_NOBODY, true);

// 执行curl会话，获取响应头信息
curl_exec($ch);

// 获取文件大小
$file_size = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);

// 关闭curl会话
curl_close($ch);

echo "文件大小：" . $file_size . " bytes";

// 使用curl下载文件
$ch = curl_init($url);
$fp = fopen($file_path, "w");

curl_setopt($ch, CURLOPT_FILE, $fp);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);

curl_exec($ch);

curl_close($ch);
fclose($fp);