Content-Disposition 属性是作为对下载文件的一个标识字段，在rfc2616 http://www.rfc-editor.org/rfc/rfc2616.pdf 章节19.5 Additional Features中

有介绍，具体介绍请看 http://www.rfc-editor.org/rfc/rfc1806.txt

字段介绍如下：

2. disposition := "Content-Disposition" ":"

3. disposition-type

4. *(";" disposition-parm)

5. disposition-type := "inline"

6. / "attachment"

7. / extension-token

8. ; values are not case-sensitive

9. disposition-parm := filename-parm / parameter

10. filename-parm := "filename" "=" value;

Content-Disposition属性有两种类型：inline 和 attachment

inline ：将文件内容直接显示在页面

1. File file = new File("rfc1806.txt");

2. String filename = file.getName();

3. response.setHeader("Content-Type","text/plain");

4. response.addHeader("Content-Disposition","inline;filename=" + new String(filename.getBytes(),"utf-8"));

5. response.addHeader("Content-Length","" + file.length());

https://img-blog.csdnimg.cn/20181113102343465.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpYW94aW9uZ19qaWF4aW4=,size_16,color_FFFFFF,t_70" width="720" />

attachment：弹出对话框让用户下载

1. File file = new File("rfc1806.txt");

2. String filename = file.getName();

3. response.setHeader("Content-Type","text/plain");

4. response.addHeader("Content-Disposition","attachment;filename=" + new String(filename.getBytes(),"utf-8"));

5. response.addHeader("Content-Length","" + file.length());

https://img-blog.csdnimg.cn/20181113102223369.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3hpYW94aW9uZ19qaWF4aW4=,size_16,color_FFFFFF,t_70" width="726" />