现在的浏览器能够识别很多文件类型(txt,pdf,jpg…),并在浏览器中自动打开

location /upload {
    add_header Content-Disposition "attachment;";
}

解决方法二

只处理指定目录下的文件

 location ~^/somepath/(.*)$ {
     add_header Content-Disposition "attachment; filename=$1";
     alias "E:/apache-tomcat-7.0.32/webapps/upload/$1";
 }