ajax与servlet传值问题

qq_33474742 2016-10-15 02:41:40

拜托各位大神帮小菜鸟看看哪里出问题了

showData.html文件：
function sendRequest() {
var XMLHttpReq=createXMLHttpRequest();
var url = "ajaxServlet.java"; //目标URI
XMLHttpReq.open("POST", url, true);
XMLHttpReq.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
XMLHttpReq.onreadystatechange = getContent;//指定响应函数
XMLHttpReq.send("xuehao="+xuehao);// 发送请求
}

ajaxservlet.java文件
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String id=request.getParameter("xuehao");
String str="";
JDBCTest jdbc=new JDBCTest();
try {
str=jdbc.query(id);
} catch (SQLException e) {
e.printStackTrace();
}
response.getWriter().println(str);//如何将str传给xmlHttpRequest对象
}

web.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns = "http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

<servlet >
<servlet-name>ajaxServlet</servlet-name>
<servlet-class>Student.src.com.ajaxServlet</servlet-class>
</servlet >

<servlet-mapping>
<servlet-name>ajaxServlet</servlet-name>
<url-pattern>/ajaxServlet</url-pattern>
</servlet-mapping>

<welcome-file-list>
<welcome-file>index.html</welcome-file>
</welcome-file-list>

</web-app>

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