- 该文为堕落的天使不再来原创。欢迎转载。
- 在尽心web开发时，可能遇到以下几种需求：（disposition配置）
- 希望某类或者某已知MIME 类型的文件（比如：*.gif;*.txt;*.htm）能够在访问时弹出“文件下载”对话框。
- 希望客户端下载时以指定文件名显示。
- 希望某文件直接在浏览器上显示而不是弹出文件下载对话框。
对于上面的需求，使用Content-Disposition属性就可以解决。下面是代码示例：
response.setHeader("Content-disposition", "attachment;filename=" + fileName)。//Content-disposition为属性名。
//attachment表示以附件方式下载。
如果要在页面中打开，则改为inline。
//filename如果为中文，则会出现乱码。解决办法有两种：
//1、使用fileName = new String(fileName.getBytes(), "ISO8859-1")语句
/* 验证content-disposition */
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String path = this.getServletContext().getRealPath("/picture/桌面壁纸.jpg");
String fileName = path.substring(path.indexOf("\\") + 1);
//1、使用fileName = new String(fileName.getBytes(), "ISO8859-1")语句
fileName = new String(fileName.getBytes(),"ISO8859-1");
// response开始发送响应头
response.setHeader("content-disposition", "attachment;filename="
+ fileName); // 基本的流操作
OutputStream out = null;
FileInputStream in = null;
try {
in = new FileInputStream(path);// 绝对路径
out = response.getOutputStream();
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) != -1) {
out.write(buf, 0, len);
}
} finally {
if (in != null) {
try {
// 关闭流
in.close();
} catch (Exception e) {
e.printStackTrace();
}
}
if (out != null) {
try {
// 关闭流
out.close();
} catch (Exception e) {
e.printStackTrace();
}
} }
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request, response);
}
//2、使用 URLEncoder.encode(fileName,"UTF-8" 语句
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String path = this.getServletContext().getRealPath(
"/picture/桌面壁纸.jpg");
String fileName = path.substring(path.lastIndexOf("\\") + 1);
// System.out.println(fileName);//桌面壁纸.jpg
/*response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");*///这样是错误的
// 发送响应头，如果文件是中文名，这要经过url编码
response.setHeader("Content-disposition", "attachment;filename="
+ URLEncoder.encode(fileName,"UTF-8")); // 下载图片
OutputStream out = null;
FileInputStream in = null;
try {
in = new FileInputStream(path);// 绝对路径
out = response.getOutputStream();
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) != -1) {
out.write(buf, 0, len);
}
} finally {
if(in != null){
try{
// 关闭流
in.close();
}catch(Exception e){
e.printStackTrace();
}
}
if(out != null){
try{
// 关闭流
out.close();
}catch(Exception e){
e.printStackTrace();
}
} } } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}