这是我第一次使用JSP和servlet。我的JSP中有一个表单，其中包含产品名称，描述等的文本输入，以及上传图像的字段。一切都存储在数据库中（但只有图像路径）。我在网上搜索了如何实现图像的东西，我终于让它工作了，但现在它不会从文本字段中读取信息。也就是说，我的变量是空的或null，即使它们应该从正确的参数中获取。
这是我的servlet：
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class AgregaProd extends HttpServlet{
public void doPost(HttpServletRequest request,HttpServletResponse response){
String nombre = request.getParameter("nombre");
String precio = request.getParameter("precio");
String catalogo = request.getParameter("catalogo");
String descripcion = request.getParameter("descripcion");
try{
String fileName="";
String imagen="";
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart) {
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
List items = upload.parseRequest(request);
Iterator iterator = items.iterator();
while (iterator.hasNext()) {
FileItem imageFile = (FileItem) iterator.next();
if(imageFile.getSize() > 100000){
return ;
}
if (!imageFile.isFormField()) {
fileName = imageFile.getName();
String fileBase = getServletContext().getInitParameter("IMAGE_FILEBASE");
File filePath = new File(fileBase + File.separator);
if (!filePath.exists()) {
boolean status = filePath.mkdirs();
}
File uploadedFile = new File(filePath + "/" + fileName);
imageFile.write(uploadedFile);
imagen=getServletContext().getInitParameter("imgsd")+"ComprasCool/imagenes/"+fileName;
}
}
}
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost/ComprasCool";
Connection con = DriverManager.getConnection(url,"root","jkDuhx+32");
Statement stat = con.createStatement();
ResultSet rs = stat.executeQuery("SELECT * FROM Producto");
RequestDispatcher disp = getServletContext().getRequestDispatcher("/agregarproducto.jsp");
int ide = 1;
int idc = 0;
switch(catalogo){
case "hogar":
idc=1;
break;
case "solares":
idc=2;
break;
case "electronicos":
idc=3;
break;
case "memorias":
idc=4;
break;
case "accesorios":
idc=5;
break;
}
if(!rs.next()){
stat.executeUpdate("INSERT INTO Producto VALUES (\"" + ide + "\",\"" + nombre + "\",\"" + descripcion + "\"," + precio + ",\"" + imagen + "\",\"" + idc + "\");");
disp = getServletContext().getRequestDispatcher("/exito.jsp");
} else {
rs.last();
ide=rs.getInt("idProducto")+1;
stat.executeUpdate("INSERT INTO Producto VALUES (\"" + ide + "\",\"" + nombre + "\",\"" + descripcion + "\"," + precio + ",\"" + imagen + "\",\"" + idc + "\");");
disp = getServletContext().getRequestDispatcher("/exito.jsp");
}
stat.close();
con.close();
if(disp!=null){
disp.forward(request,response);
}
}catch(Exception e){
e.printStackTrace();
}
}
}
这是我的JSP：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Compras Cool</title>
<link href="style.css" rel="stylesheet" type="text/css" />
</head>
<div id="header">
<div id="logo"><a href="index.jsp"><img src="logo.gif" width="380" height="84" /></a>
</div>
<div id="search">
<form id="form1" name="form1" method="post" action="./buscar">
<input type="text" name="searchbar" class="searchbar" id="searchbar"/>
<input type="submit" name="searchbtn" class="searchbtn" id="searchbtn" value="Buscar" />
</form>
</div>
<div id="userstuff"><a href="admin.jsp">logout</a>
</div>
<div id="nav"><a href="./hogarAdmin" target="_self" class="nav_link">Hogar</a> <a href="./solaresAdmin" target="_self" class="nav_link">Solares</a> <a href="./electronicosAdmin" target="_self" class="nav_link">Electronicos</a> <a href="./memoriasAdmin" target="_self" class="nav_link">Memorias</a> <a href="./accesoriosAdmin" target="_self" class="nav_link">Accesorios</a><a href="ordenes.jsp" target="_self" class="nav_link">Ordenes</a></div>
<div id="content">
<div id="registro">
<h1>Nuevo producto</h1>
<form id="form2" name="form2" method="POST" action="./registraProducto" runat="server" enctype="multipart/form-data">
<p>
<label>Nombre:
<input type="text" name="nombre" id="textfield4" size="20" />
</label>
</p>
<p>
<label>Precio:
<input type="text" name="precio" id="textfield6" size="20"/>
</label>
</p>
<p>
<label>Catalogo: </label>
<select name="catalogo" id="select" class="select">
<option value="hogar">Hogar</option>
<option value="solares">Solares</option>
<option value="electronicos">Electronicos</option>
<option value="memorias">Memorias</option>
<option value="accesorios">Accesorios</option>
</select>
</p>
<label>Descripcion:</label><p>
<textarea name="descripcion" class="des"></textarea>
<p><label>Imagen: </label>
<input type="file" name="fileName" value="" accept="image/*" runat="server">
<p></p>
<p align="right">
<input name="registrobtn" type="submit" class="loginbtn" value="Agregar" />
</form>
</div>
</div>
<div id="footer">©Compras Cool 2014
<p>Acerca<font face="Arial"> | </font><a href="contacto.jsp">Contacto</a><font face="Arial"> | </font>Terminos y condiciones</p>
</div>
</body>
</html>
提前致谢!!
答案 0 :(得分：0)
使用FileItem#getFieldName()获取输入字段的名称，使用FileItem#getString()获取输入字段的值。
<强>解决方案：
创建两个实用程序方法，一个用于常规输入字段，另一个用于文件输入字段数据。像：
// Process a regular form field
private void processFormField(FileItem item){
if (item.isFormField()) {
String name = item.getFieldName();
String value = item.getString();
}
}
// Process a file upload
private void processUploadedFile(FileItem imageFile){
if (!imageFile.isFormField()) {
//your existing file upload code.
}
}
然后，在while循环中使用上面的方法来获取如下数据：
while (iterator.hasNext()) {
FileItem item = iterator.next();
if (item.isFormField()) {
processFormField(item);
} else {
processUploadedFile(item);
}
}