PHP使用curl获取远程网页内容，并转换编码

代码：【复制】 
function get_page_code_with_charset($url, $charset = 'UTF-8') {
    global $_HTTPHEADER, $_REFERER;
    global $_USERAGENT;
    try {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_HTTPHEADER, $_HTTPHEADER);
        curl_setopt($ch, CURLOPT_ENCODING, 'gzip, deflate, sdch');
        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($ch, CURLOPT_MAXREDIRS, 3);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($ch, CURLOPT_FRESH_CONNECT, true);
        curl_setopt($ch, CURLOPT_FORBID_REUSE, true);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); //设置是否将响应结果存入变量，1是存入，0是直接echo
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 1); //在发起连接前等待的时间，如果设置为0，则无限等待。
        curl_setopt($ch, CURLOPT_TIMEOUT, 15);       //允许执行的最长秒数。
        curl_setopt($ch, CURLOPT_USERAGENT, $_USERAGENT);
        curl_setopt($ch, CURLOPT_REFERER, $_REFERER); //伪造来源页面
        curl_setopt($ch, CURLOPT_HEADER, true);       // 获取头部信息
        curl_setopt($ch, CURLOPT_URL, $url);
        if (curl_errno($ch)) {
            return false;
        } else {
            $html = curl_exec($ch);
            $httpStatusCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);            
            if($httpStatusCode == 200) {
                // 分离响应头和响应体
                $headerInfo = curl_getinfo($ch, CURLINFO_HEADER_SIZE); // 获取响应头的长度
                $header = substr($html, 0, $headerInfo); // 提取响应头
                $body = substr($html, $headerInfo); // 提取响应体
                $contentLength = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);
                
                /* 
                // 方案二 解析 Content-Length 字段，判断是否为 0
                $contentLength = 0;
                // // 按行分割响应头，遍历查找 Content-Length
                $headerLines = explode("\r\n", $header);
                foreach ($headerLines as $line) {
                    // 忽略大小写，匹配 Content-Length 字段
                    if (stripos($line, "Content-Length:") !== false) {
                    //if (preg_match('/^Content-Length:/i', $line)) {
                        提取字段值并去除空格
                        $parts = explode(":", $line);
                        $contentLength = trim($parts[1]);
                        break;
                    }
                }
                */

                if($contentLength == 0) {
                    return false;
                }
                else {
                    // 转换字符集
                    if ($charset != 'UTF-8') {
                        $body = mb_convert_encoding($body, 'UTF-8', $charset);
                    }
                    return $body;
                }
            }
            else {
                return false;
            }
        }
        curl_close($ch);
    } catch (Exception $e) {
        return false;
    }
}