在使用 PHP 做一些简单爬虫的时候,我们经常会遇到要下载远程图片,所以下面来简单实现这个需求。 1.使用 curl 比如我们有下面这两张图片: $images = [ 'https://dn-laravist.qbox.me/2015-09-22_00-17-06j.png', 'https://dn-laravist.qbox.me/2015-09-23_00-58-03j.png' ]; 第一步,我们可以直接来使用最简单的代码实现: function download($url, $path = 'images/') { $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30); $file = curl_exec($ch); curl_close($ch); $filename = pathinfo($url, PATHINFO_BASENAME); $resource = fopen($path . $filename, 'a'); fwrite($resource, $file); fclose($resource); } 那在下载远程图片的时候就可以这样: foreach ( $images as $url ) { download($url); } 2.封装一个类 class Spider { public function downloadImage($url, $path = 'images/') { $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30); $file = curl_exec($ch); curl_close($ch); $filename = pathinfo($url, PATHINFO_BASENAME); $resource = fopen($path . $filename, 'a'); fwrite($resource, $file); fclose($resource); } } 在者,我们还可以这样稍微优化一下: public function downloadImage($url, $path='images/') { $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30); $file = curl_exec($ch); curl_close($ch); $this->saveAsImage($url, $file, $path); } private function saveAsImage($url, $file, $path) { $filename = pathinfo($url, PATHINFO_BASENAME); $resource = fopen($path . $filename, 'a'); fwrite($resource, $file); fclose($resource); } 封装成类之后,我们可以这样调用代码来下载图片: $spider = new Spider(); foreach ( $images as $url ) { $spider->downloadImage($url); } 这样,对付基本的远程图片下载就OK了。 希望本文所述对大家程序设计有所帮助。 |