Javascript 使用Jquery的Submit和$post时，程序的行为不同

我正在经历一个混乱的情况，当点击按钮时，pdf应该被下载。我的设计和要求如下：

点击按钮

显示带有两个按钮的确认框

保存

和

打开

如果选择“保存”，则pdf应保存在本地计算机上

第三点是我面临的问题，因为没有确认框。在这里，当使用

提交按钮提交表单时（无确认框），将下载文件。代码如下：

<button type="submit" id="Export">xxx_tutorial</button>

Servlet：

package com.testcase.testing;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class button
 */
@WebServlet("/button")
public class button extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public button() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request, response);
        }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub

        response.getWriter().append(request.getParameter("param"));
        performTask(request,response);
    }

    private void performTask(HttpServletRequest request, HttpServletResponse response) throws ServletException,
    IOException {

        String pdfFileName="";

        if(request.getParameter("param")==null){

    }
    else if(request.getParameter("param").matches("sap_webi_tutorial")){
        System.out.println("in create pdf file name part");
        pdfFileName = "/"+request.getParameter("param")+".pdf";
    }
        else{

        }

String contextPath = getServletContext().getRealPath(File.separator);
File pdfFile = new File(contextPath + "/xxx_tutorial.pdf"); 
response.setContentType("application/pdf");
response.addHeader("Content-Disposition", "attachment; filename=" + "/xxx_tutorial.pdf");
response.setContentLength((int) pdfFile.length());

FileInputStream fileInputStream = new FileInputStream(pdfFile);
PrintWriter responseOutputStream = response.getWriter();
int bytes;
    while ((bytes = fileInputStream.read()) != -1) {
    responseOutputStream.write(bytes);
}
fileInputStream.close();
responseOutputStream.flush();
responseOutputStream.close();
    }
}

如果您
submit
表单，浏览器中显示的页面将收到该操作的结果-这就像单击一个链接

调用
$.post（）
将在后台发送数据，并将结果数据返回到回调函数（在您发布的代码中为空）。所以你必须在这个函数中处理结果

有关背景信息，请参阅

也许您可以执行您的逻辑，然后不再调用
$.post（）
，而只需从JavaScript代码中重新提交表单

选中此选项可直接提交表单：

先生，谢谢您的回答。。。实际上，我的下载代码是在servlet中的，所以我刚刚将数据传递给servlet，但是我如何在jsp中捕获下载文件呢？有什么方法可以做到这一点，因为我尝试使用javascript，但我的要求是我需要有一个自定义的确认框，这只能通过Jquery实现
package com.testcase.testing;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class button
 */
@WebServlet("/button")
public class button extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public button() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request, response);
        }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub

        response.getWriter().append(request.getParameter("param"));
        performTask(request,response);
    }

    private void performTask(HttpServletRequest request, HttpServletResponse response) throws ServletException,
    IOException {

        String pdfFileName="";

        if(request.getParameter("param")==null){

    }
    else if(request.getParameter("param").matches("sap_webi_tutorial")){
        System.out.println("in create pdf file name part");
        pdfFileName = "/"+request.getParameter("param")+".pdf";
    }
        else{

        }

String contextPath = getServletContext().getRealPath(File.separator);
File pdfFile = new File(contextPath + "/xxx_tutorial.pdf"); 
response.setContentType("application/pdf");
response.addHeader("Content-Disposition", "attachment; filename=" + "/xxx_tutorial.pdf");
response.setContentLength((int) pdfFile.length());

FileInputStream fileInputStream = new FileInputStream(pdfFile);
PrintWriter responseOutputStream = response.getWriter();
int bytes;
    while ((bytes = fileInputStream.read()) != -1) {
    responseOutputStream.write(bytes);
}
fileInputStream.close();
responseOutputStream.flush();
responseOutputStream.close();
    }
}