PHP 下载远程图片

方法一：file_get_contents

/**-- 下载远程文件 --**/
    function down_img($url){
        set_time_limit(60);
	if($url==""){
            return false;
	}
	$ext=strrchr($url,".");
	if($ext!=".gif" && $ext!=".jpg" && $ext!=".png" && $ext!=".jpeg"){
            return false;
	}
	if(!file_exists($this->uploadpath)){
            dir_create($this->uploadpath);
	}	
	$filename=$this->getname($ext);
	$img = file_get_contents($url);
	$fp2=@fopen($this->uploadpath.$filename, "a");   //此处可加上图片存放路径
	fwrite($fp2,$img);
	fclose($fp2);
        /*
	$imgwh=getimagesize($this->uploadpath.$filename);
	if($imgwh[0]>480 || $imgwh[1]>480){		
		$this->image->thumb($filename, 480, 480);
	}*/	
	return $this->urlpic.$filename;   //返回新的图片名称
    }
    /**-- 下载远程ICON .175x175-75.jpg  .100x100-75.jpg 350x350-75.jpg 512x512-75.jpg --**/
    function down_icon($url,$size){
	if($url==""):return false;endif;
	$ext='.jpg';
	$num=strrpos($url,'.');
	$data = substr($url, 0,$num); 
	$data=$data.$size;
	
	if(!file_exists($this->uploadpath)){
            dir_create($this->uploadpath);
	}	
	$filename=$this->getname($ext);
	$img = file_get_contents($data);
	$fp2=@fopen($this->uploadpath.$filename, "a");   //此处可加上图片存放路径
	fwrite($fp2,$img);
	fclose($fp2);
	return $this->urlpic.$filename;   //返回新的图片名称
    }
    /**-- 获取附件名称 @param $fileext 附件扩展名 --**/
    function getname($fileext){
        return date('Ymdhis').rand(100, 999).$fileext;
    }

方法二：redefile

/**-- 下载远程文件 --**/
    function down_img($url){
        set_time_limit(60);
		if($url==""){
				return false;
		}
		$ext=strrchr($url,".");
		if($ext!=".gif" && $ext!=".jpg" && $ext!=".png" && $ext!=".jpeg"){
				return false;
		}
		if(!file_exists($this->uploadpath)){
				dir_create($this->uploadpath);
		}	
		$filename=$this->getname($ext);
		ob_start();    //开启缓冲区
			
			$opts = array(  
				'http'=>array(  
					'method'=>"GET",  
					'timeout'=>25,   
				)  
			);  
			$context = stream_context_create($opts);  
			
			readfile($url, false, $context);  
		$img = ob_get_contents();
		ob_end_clean();
		$fp2=@fopen($this->uploadpath.$filename, "a");   //此处可加上图片存放路径
		fwrite($fp2,$img);
		fclose($fp2);
			/*
		$imgwh=getimagesize($this->uploadpath.$filename);
		if($imgwh[0]>480 || $imgwh[1]>480){		
			$this->image->thumb($filename, 480, 480);
		}*/	
		return $this->urlpic.$filename;   //返回新的图片名称
    }
    /**-- 下载远程ICON .175x175-75.jpg  .100x100-75.jpg 350x350-75.jpg 512x512-75.jpg --**/
    function down_icon($url,$size){
		if($url==""):return false;endif;
		$ext='.jpg';
		$num=strrpos($url,'.');
		$data = substr($url, 0,$num); 
		$data=$data.$size;
		
		if(!file_exists($this->uploadpath)){
			dir_create($this->uploadpath);
		}	
		$filename=$this->getname($ext);
		ob_start();
		readfile($data);
		$img = ob_get_contents();
		ob_end_clean();

		$fp2=@fopen($this->uploadpath.$filename, "a");   //此处可加上图片存放路径
		fwrite($fp2,$img);
		fclose($fp2);
		
		return $this->urlpic.$filename;   //返回新的图片名称
    }
    /**-- 获取附件名称 @param $fileext 附件扩展名 --**/
    function getname($fileext){
        return date('Ymdhis').rand(100, 999).$fileext;
    }