一、需求

页面中点击下载图片

二、实现

protected function pageLoad(){$filePath = $_GET['file'];$host = $_SERVER['HTTP_HOST'];$file =  'http://'.$host.$filePath;$fileName = basename($filePath);$content = file_get_contents($file);ob_clean();$suffixArr = explode('.', $fileName);$suffix = strtolower($suffixArr[count($suffixArr)-1]);$suffixArr[count($suffixArr)-2] .= time();$fileName = implode('.', $suffixArr);$this->download($suffix, $content, $fileName);}private function download($extension,$content,$fileName=''){ob_clean();if($content){switch ($extension){case 'jpg':case 'jpeg':case 'jpe':case 'jfif':header('Content-Type: image/jpeg');if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'png':header('Content-Type: image/png');if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'bmp':header('Content-Type: image/bmp');if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'gif':header('Content-Type: image/gif');if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'tif':case 'tiff':header('Content-Type: image/tiff');if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'swf':header("Content-type: application/x-shockwave-flash");if ($fileName){header('Content-Disposition: attachment; filename='.$fileName);}break;case 'doc':case 'docx':case 'ppt':case 'pptx':$fileName = !empty($fileName)? $fileName:'';header("Content-type: application/octet-stream");header("Accept-Ranges: bytes");header('Content-Disposition: attachment; filename='.$fileName);header("Pragma:no-cache");header("Expires:0");break;case 'pdf':$fileName = !empty($fileName)? $fileName:'';header("Content-type: application/octet-stream");header("Accept-Ranges: bytes");header('Content-Disposition: attachment; filename='.$fileName);header("Pragma:no-cache");header("Expires:0");break;case 'txt':if ($fileName){header("Content-type: application/octet-stream");header("Accept-Ranges: bytes");header('Content-Disposition: attachment; filename='.$fileName);header("Pragma:no-cache");header("Expires:0");}break;case 'html':header("Cache-Control: no-cache, must-revalidate");header("Pragma: no-cache");header("Content-Type: application/force-download");header("Content-type: text/html");header("Content-Disposition: attachment; filename=".$fileName);header("Content-Description: PHP5 Generated Data");break;case 'xls':case 'xlsx':$fileName = !empty($fileName)? $fileName:'';header("Content-type:application/octet-stream");header("Accept-Ranges:bytes");header("Content-type:application/vnd.ms-excel");header('Content-Disposition: attachment;filename='.$fileName);header("Pragma: no-cache");header("Expires: 0");break;}}echo $content;exit;}