步驟:
1,匹配URL中的主機名稱和檔案部分
2,建立socket並串連到目標伺服器
3,構造HTTP請求並發送
4,讀取HTTP響應並解析
5,儲存內容到檔案並關閉socket串連
代碼實現如下:
<?php/* * 使用socket擷取遠端資源(網頁,圖片等) * url 資源URL * savepath 資源的儲存路徑 * return true/false */function get_remote_picture($url,$savepath="./"){ set_time_limit(0); $pattern = '/(http:\/\/)?([^\/]+)(.+)/'; $res = preg_match($pattern, $url, $matches); if($res == 0){ return false; } $host = "";//主機名稱 $file = "";//請求的檔案 if(count($matches) == 3){ $host = $matches[1]; $file = $matches[2]; }else if(count($matches) == 4){ $host = $matches[2]; $file = $matches[3]; }else{ return false; } $socket = socket_create(AF_INET,SOCK_STREAM,SOL_TCP); $res = socket_connect($socket,gethostbyname($host),80); if(!$res){ //echo socket_strerror(socket_last_error($socket)); socket_close($socket); return false; } $request = ""; $request .= "GET $file HTTP/1.1\r\n"; $request .= "Host: $host\r\n"; $request .= "Connection: close\r\n\r\n"; $len = socket_write($socket,$request); $response = ""; while($buf=socket_read($socket,512)){ if(strlen($buf) == 0){ break; } $response .= $buf; } if(strpos($response,"\r\n\r\n")){ $arr = explode("\r\n\r\n",$response); if(!file_exists($savepath)){ @mkdir($savepath); } $savepath = rtrim($savepath,'/').'/'; file_put_contents($savepath.basename($file),$arr[1]); }else{ socket_close($socket); return false; } socket_close($socket); return true;} /* 擷取百度logo */$url = "http://su.bdimg.com/static/superplus/img/logo_white.png";$result = get_remote_picture($url);if($result){ echo 'get remote picture success';}else{ echo 'get remote picture failed';}