PHP 使用curl下载远程图片

php下载远程图片

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

将这个基本的功能封装到一个类中：

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);
}

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参考：https://zhuanlan.zhihu.com/p/27484500