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php图片处理函数获取类型及扩展名实例_php技巧

May 16, 2016 pm 08:31 PM
phpfunctionImage processingextension nametypeObtain

本文实例讲述了php图片处理函数获取类型及扩展名的方法。分享给大家供大家参考。

具体实现代码如下:

复制代码 代码如下:
image_type=image_type_to_mime_type(imagetype_png);   //获取png的mime类型
echo $image_type;           //输出结果
//
 
$file = '1.jpg';
$image = imagecreatefromjpeg($file);
header('content-type: ' . image_type_to_mime_type(imagetype_wbmp));
$fp=fopen($file,r);
fpassthru($fp);
image2wbmp($image,"1.bmp"); // output the stream directly
 
//image_type_to_extension. (php教程 5). image_type_to_extension — 取得图像类型的文件 后缀 ... warning. 本函数暂无文档
 
$file_ext=image_type_to_extension("1.jpg");
echo $file_ext;
//
 
$filename="1.jpg";         //定义图像文件
$size=getimagesize($filename);      //获取图像的大小
$fp=fopen($filename,"rb");        //打开文件
if($size && $fp)          //如果成功打开
{
  header("content-type: {$size['mime']}");     //输出文件头信息
  fpassthru($fp);         //输出文件内容
  exit;           //中止操作
}
else
{
  echo "文件打开失败,或者指定的不是图像文件";   //输出错误信息
}

希望本文所述对大家的PHP程序设计有所帮助。

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