我正在以表格形式上传文件，该表格还包含一些textfields我在文本字段中输入的值。当我单击上传按钮时，我希望这个值保持不变。还有一个保存按钮，当我单击此按钮时，上传的文件应该保存在数据库中。谁能帮我吗？
JSP 文件在这里：
<body>
<form action="./upload" enctype="multipart/form-data" >ID: <input type="text" name="id" value="" />Name: <input type="text" name="name" value="" />
<input name="uploaded" type="file" />
<input name="save" type="submit" value="Upload" />
<input type="submit" value="save1" name="save" /></form>
</body>
我需要servlet中的业务逻辑..
嘿，您是说单击“上传”按钮时应该存在文本字段值。你不必做这件事。默认情况下它会在那里。你应该它会毒死人吗？请提及您的确切要求。
您的选择是：
最简单的选择是 IFRAME。
请参阅没有规定使用 value 属性保留文件字段数据。
package comunity.stackoverflow.test;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class TestController
*/
public class TestController extends HttpServlet {
private static final long serialVersionUID = 1L;
public TestController() {
super();
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
process(request, response);
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
process(request, response);
}
private void process(HttpServletRequest request,
HttpServletResponse response) {
storeInRequest(request, "id");
storeInRequest(request, "name");
storeInRequest(request, "uploaded");
// write your upload logic here then navigate to the same page;
try {
request.getRequestDispatcher("/test.jsp").forward(request, response);
} catch (ServletException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
private void storeInRequest(HttpServletRequest request,String param){
String val = request.getParameter(param);
if(param!=null && !param.isEmpty()){
System.out.println(val);
request.setAttribute(param, val);
}
}
}
使用 standard.jat 和 jstl.jar
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form action="upload.do" enctype="multipart/form-data" >
ID: <input type="text" name="id" value="${id}"/>
Name: <input type="text" name="name" value="${name}" />
<input name="uploaded" type="file" />
<input name="save" type="submit" value="Upload" />
<input type="submit" value="save1" name="save" /></form>
</body>
</html>
使用此 JSP 文件。它可能会解决您的问题。
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form action="upload.do" enctype="multipart/form-data" >
ID: <input type="text" name="id" value="${id}"/><br/>
Name: <input type="text" name="name" value="${name}" /><br/>
<input type="file" id="selectedFile" style="display: none;" />
<input type="text" name="uploaded" id="uploaded" value="${uploaded}" readonly="readonly" size="60">
<input type="button" value="Browse..." onclick="mymethod()" /><br/>
<input name="save" type="submit" value="Upload" />
<input type="submit" value="save1" name="save" /></form>
</body>
<script type="text/javascript">
function mymethod(){
document.getElementById('selectedFile').click();
var val = document.getElementById('selectedFile').value;
document.getElementById('uploaded').value = val;
}
</script>
</html>