关于Servlet读取Html表单数据的问题
package cn.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ShowParameters extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println("<HEAD><TITLE>Reading AllRequest Parameters</TITLE></HEAD>");
out.println("<BODY>");
out.print("<h1 align=center>");
out.print("Reading AllRequest Parameters");
out.println("</h1>");
Enumeration paramNames=request.getParameterNames();
int i=0;
while(paramNames.hasMoreElements()){
i++;
String paramName=(String)paramNames.nextElement();
out.print("<p align=center>"+i+" "+paramName+"</p>");
}
out.println("</BODY>");
out.println("</HTML>");
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>ShowParametersFrom.html</title>
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<!--<link rel="stylesheet" type="text/css" href="./styles.css">-->
</head>
<body>
<h1 align="center">
A Sample FORM using POST
</h1>
<form action="servlet/ShowParameters" method="post">
Item Number:
<input type="text" name="itemNum" />
<br />
Quantity:
<input type="text" name="quantity" />
<br />
Price Each:
<input type="text" name="price" value="$" />
<br />
<hr />
First Name:
<input type="text" name="firstname" />
<br />
Last Name:
<input type="text" name="lastname" />
<br />
Middle Initial:
<input type="text" name="intitial" />
<br />
Shipping Address:
<textarea name="address" rows=3 cols=40></textarea>
<br />
Credit Card:
<br />
<label>
<input type="radio" name="cardType" id="cardType_0" />
Visa
</label>
<br />
<label>
<input type="radio" name="cardType" id="cardType_1" />
Master
</label>
<br />
<label>
<input type="radio" name="cardType" id="cardType_2" />
American Express
</label>
<br />
<label>
<input type="radio" name="cardType" id="cardType_3" />
Discover
</label>
<br />
<label>
<input type="radio" name="cardType" id="cardType_4" />
Java SmartCard
</label>
<br />
Credit Card Number:
<input type="password" name="cardNum" />
<br />
Repeadt Credit Card Number:
<input type="password" name="cardNum" />
<br />
<center>
<input type="submit" value="Submit Order" />
</center>
</form>
</body>
</html>
为什么我的paramNames读取不到cardType表单数据，其他的都可以读到
你可以用一个for循环把数组内容输出
[解决办法]
ＬＺ
<input type="radio" name="cardType" id="cardType_4" />
你这不是单选的，只会得到一个值的，就直接取就行了，关键是你选了没，这种单选会给一个默认值，你想选就选，不选就会得到默认值。否则不选 的话，得到的是空值，再看看吧
[解决办法]
你所有的radio都没设值，怎么取？
不管选没选，后台取到的都是空啊