Content-Disposition

文件下载响应头的设置

content-type 指示响应内容的格式

content-disposition 指示如何处理响应内容。

一般有两种方式：

• inline：直接在页面显示
• attchment：以附件形式下载

/**
 * 设置强制下载
 * @param fileName
 * @param response
 */
@RequestMapping("/downOpen")
public void downOpen(@RequestParam("fileName") String fileName,HttpServletResponse response){
    String fix = fileName.substring(fileName.lastIndexOf("."), fileName.length());
    response.setHeader("Content-Disposition", "attachment;filename=" + System.currentTimeMillis()+fix);
    response.setContentType("application/force-download");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.downloadOpen(fileName,response);
}

/**
 * 设置Content-Disposition ：inline 无效直接下载，不打开
 * @param fileName
 * @param response
 */
@RequestMapping("/forceDownInline")
public void forceDownInline(@RequestParam("fileName") String fileName,HttpServletResponse response){
    String fix = fileName.substring(fileName.lastIndexOf("."), fileName.length());
    response.setHeader("Content-Disposition", "inline;filename=" + System.currentTimeMillis()+fix);
    response.setContentType("application/force-download");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.downloadOpen(fileName,response);
}

/**
 * 不设置 Content-Disposition 在页面显示
 * @param url
 * @param response
 */
@RequestMapping("/urlOpen/{url}")
public void urlOpen(@PathVariable("url") String url, HttpServletResponse response){
    response.setContentType("image/png");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.urlOpen(url,response);
}
/**
 * inline：直接在页面显示
 * @param url
 * @param response
 */
@RequestMapping("/urlOpenInline/{url}")
public void urlOpenInline(@PathVariable("url") String url, HttpServletResponse response){
    response.setHeader("Content-Disposition", "inline;filename=" + System.currentTimeMillis()+".png");
    response.setContentType("image/png");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.urlOpen(url,response);
}

/**
 * 附件形式下载,不打开
 * @param url
 * @param response
 */
@RequestMapping("/urlDownAttachment/{url}")
public void urlDownAttachment(@PathVariable("url") String url, HttpServletResponse response){
    response.setHeader("Content-Disposition", "attachment;filename=" + System.currentTimeMillis()+".png");
    response.setContentType("image/png");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.urlOpen(url,response);
}

/**
 * attachment:以附件形式下载，不打开
 * @param url
 * @param response
 */
@RequestMapping("/downAttachment/{url}")
public void downAttachment(@PathVariable("url") String url, HttpServletResponse response){
    response.setHeader("Content-Disposition", "attachment;filename=" + System.currentTimeMillis()+".png");
    response.setContentType("application/octet-stream");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.urlOpen(url,response);
}

/**
 * 设置Content-Disposition ：inline 无效 直接下载 不打开
 * @param url
 * @param response
 */
@RequestMapping("/streamInline/{url}")
public void streamInline(@PathVariable("url") String url, HttpServletResponse response){
    response.setHeader("Content-Disposition", "inline;filename=" + System.currentTimeMillis()+".png");
    response.setContentType("application/octet-stream");
    response.setCharacterEncoding("UTF-8");
    FtpUtil.urlOpen(url,response);
}

以上这几种设置方式，在<img> 标签中都会展示出图片，不同的是在浏览器访问，

<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为二进制流数据-->
    <img alt="downOpen" src="http://localhost:8080/ftp/downOpen?fileName=1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为图片本图-->
    <img alt="urlOpen" src="http://localhost:8080/ftp/urlOpen/1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为图片本图-->
    <img alt="urlOpenInline" src="http://localhost:8080/ftp/urlOpenInline/1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为图片本图-->
    <img alt="downAttachment" src="http://localhost:8080/ftp/downAttachment/1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为图片本图-->
    <img alt="urlDownAttachment" src="http://localhost:8080/ftp/urlDownAttachment/1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为图片本图-->
    <img alt="streamInline" src="http://localhost:8080/ftp/streamInline/1677072114406.jpeg"/>
</div>
<div style="width: 100px;height: 100px;">
    <!--显示有效，预览为二进制流数据-->
    <img alt="streamInline" src="http://localhost:8080/ftp/forceDownInline?fileName=1677072114406.jpeg"/>
</div>

在<img>标签中，预览会有不同

设置

response.setContentType("application/octet-stream"); 预览为二进制流数据

其他设置预览为图片

在浏览器访问url时设置

Content-Disposition ：attachment 会下载，不打开

Content-Disposition ：inline 不下载，直接打开