PHP 下载远程网页图片并且保存在本地实例

//URL是远程的完整图片地址，不能为空, $filename 是另存为的图片名字
//默认把图片放在以此脚本相同的目录里
function GrabImage($url,$filename=""){
if($url == ""){
return false;
}

$ext=strrchr($url,".");

if($ext != ".gif" && $ext != ".jpg" && $ext != ".bmp" && $ext != ".png"){
echo "格式不支持！";
return false;
}

if($filename == ""){
$filename = time()."$ext";
}

ob_start();
readfile($url);
$img=ob_get_contents();
ob_end_clean();
$size=strlen($img);
$fp2=fopen($filename,"a");
if(fwrite($fp2,$img) === false){
echo "不能写入文件".$filename;
exit();
}else{
echo "保存图片成功！";
}
fclose($fp2);
return $filename;

}
//测试
GrabImage("/logo.png","as.png");
?>

function DownImageKeep($gurl, $rfurl, $filename, $gcookie=”", $JumpCount=0, $maxtime=30)
{
$urlinfos = GetHostInfo($gurl);
$ghost = trim($urlinfos['host']);
if($ghost==”)
{
return FALSE;
}
$gquery = $urlinfos['query'];
if($gcookie==”" && !empty($rfurl))
{
$gcookie = RefurlCookie($rfurl);
}
$sessionQuery = “GET $gquery HTTP/1.1rn”;
$sessionQuery .= “Host: $ghostrn”;
$sessionQuery .= “Referer: $rfurlrn”;
$sessionQuery .= “Accept: */*rn”;
$sessionQuery .= “User-Agent: Mozilla/4.0 (compatible; MSIE 5.00; Windows 98)rn”;
if($gcookie!=”" && !preg_match(“/[rn]/”, $gcookie))
{
$sessionQuery .= $gcookie.”rn”;
}
$sessionQuery .= “Connection: Keep-Alivernrn”;
$errno = “”;
$errstr = “”;
$m_fp = fsockopen($ghost, 80, $errno, $errstr,10);
fwrite($m_fp,$sessionQuery);
$lnum = 0;

//获取应答头
$m_httphead = Array();
$httpstas = explode(” “,fgets($m_fp,256));
$m_httphead["http-edition"] = trim($httpstas[0]);
$m_httphead["http-state"] = trim($httpstas[1]);
while(!feof($m_fp))
{
$line = trim(fgets($m_fp,256));
if($line == “” || $lnum>100)
{
break;
}
$hkey = “”;
$hvalue = “”;
$v = 0;
for($i=0; $i {
if($v==1)
{
$hvalue .= $line[$i];
}
if($line[$i]==”:”)
{
$v = 1;
}
if($v==0)
{
$hkey .= $line[$i];
}
}
$hkey = trim($hkey);
if($hkey!=”")
{
$m_httphead[strtolower($hkey)] = trim($hvalue);
}
}

if(preg_match(“/^3/”, $m_httphead["http-state"]))
{
if(isset($m_httphead["location"]) && $JumpCount<3) { $JumpCount++; DownImageKeep($gurl,$rfurl,$filename,$gcookie,$JumpCount); } else { return FALSE; } } if(!preg_match(“/^2/”, $m_httphead["http-state"])) { return FALSE; } if(!isset($m_httphead)) { return FALSE; } $contentLength = $m_httphead['content-length']; //保存图片 $fp = fopen($filename,”w”) or die(“写入文件：{$filename} 失败！”); $i=0; $okdata = “”; $starttime = time(); while(!feof($m_fp)) { $okdata .= fgetc($m_fp); $i++; //超时退出 if(time()-$starttime>$maxtime)
{
break;
}

//到达指定大小结束
if($i >= $contentLength)
{
break;
}
}
if($okdata!=”")
{
fwrite($fp,$okdata);
}
fclose($fp);
if($okdata==”")
{
@unlink($filename);
fclose($m_fp);
return FALSE;
}
fclose($m_fp);
return TRUE;
}
//获得网址的host和query部份
function GetHostInfo($gurl)
{
$gurl = preg_replace(“/^http:///i”, “”, trim($gurl));
$garr['host'] = preg_replace(“//(.*)$/i”, “”, $gurl);
$garr['query'] = “/”.preg_replace(“/^([^/]*)//i”, “”, $gurl);
return $garr;
}
//获得页面返回的Cookie信息
function RefurlCookie($gurl)
{
global $gcookie,$lastRfurl;
$gurl = trim($gurl);
if(!empty($gcookie) && $lastRfurl==$gurl)
{
return $gcookie;
}
else
{
$lastRfurl=$gurl;
}
if(trim($gurl)==”)
{
return ”;
}
$urlinfos = GetHostInfo($gurl);
$ghost = $urlinfos['host'];
$gquery = $urlinfos['query'];
$sessionQuery = “GET $gquery HTTP/1.1rn”;
$sessionQuery .= “Host: $ghostrn”;
$sessionQuery .= “Accept: */*rn”;
$sessionQuery .= “User-Agent: Mozilla/4.0 (compatible; MSIE 5.00; Windows 98)rn”;
$sessionQuery .= “Connection: Closernrn”;
$errno = “”;
$errstr = “”;
$m_fp = fsockopen($ghost, 80, $errno, $errstr,10) or die($ghost.’
‘);
fwrite($m_fp,$sessionQuery);
$lnum = 0;

//获取详细应答头
$gcookie = “”;
while(!feof($m_fp))
{
$line = trim(fgets($m_fp,256));
if($line == “” || $lnum>100)
{
break;
}
else
{
if(preg_match(“/^cookie/i”, $line))
{
$gcookie = $line;
break;
}
}
}
fclose($m_fp);
return $gcookie;
}