通过javascript函数传递到servlet的参数

Parameter passing through javascript function to a servlet

本文关键字:servlet 参数 javascript 函数 通过      更新时间:2023-09-26

我们可以通过javascript函数将参数传递给servlet吗?

这是我的代码,我试图在点击"获取作者名称"按钮时将addUpdate.jsp的javascript函数中的值传递给BookServlet。当我点击该按钮时,它成功地转到了servlet,但它没有接受我通过函数传递的参数。。

addUpdate.jsp:

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
    <%@page import="com.fulcrum.obl.model.Author"%>
    <%@page import="java.util.ArrayList"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
    <%@page isELIgnored="false" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script type="text/javascript">
function submitAddForm(button) {
    alert("hiee");
    if(button.value=="Get Authors names") {
        alert("in iff");
        //alert(document.getElementById("bookDetails"));
        document.getElementById("bookDetails").action="BookServlet?authorNames=authorNames";
    }
}
function setAuthorsNames() {
     var x =document.getElementById("select");
     var myList = document.getElementById("selected");
     var myOption = document.createElement("Option");
    for(var i=0;i < x.options.length;i++) {
         if(x.options[i].selected ==true){
             alert("in if");
              myOption.text = x.options[i].value;
              myOption.value = x.options[i].value;
              myList.add(myOption);
              x.remove(x.options.selectedIndex);
          }
    }
}


</script>
</head>
<body>
<h4>Book Form</h4>
<form  id="bookDetails">
Long Title : <input type="text" name="longT">
<br>
<br>
Short Title : <input type="text" name="shortT" />
<br>
<br>
Isbn :  <input type="text" name="shortT" />
<br>
<br>
Date of Publication : <input type="text" name="dop" />
<br>
<br>
No of pages : <input type="text" name="nop" />
<br>
<br>
bound type : 
<select id="boundType">
  <option value="0">HardBound</option>
  <option value="1">SoftBound</option>
</select>
<br>
<br>
DVD Availability :
<select id="dvd">
  <option value="y">Yes</option>
  <option value="n">No</option>
</select>
<br>
<br>
No of copies available :  <input type="text" name="noca" />
<br>
<br>
<% 
if(request.getAttribute("authorNamesList") != null) {
    ArrayList<Author> booksList = (ArrayList<Author>)request.getAttribute("authorNamesList");
%>
<select id="select" size="6">
 <c:forEach items="${authorNamesList}" var="authorNames">
<option value="${authorNames.firstName}">${authorNames.firstName}</option>
</c:forEach>
</select>
<%
}
%>
<select size="6"  id="selected">
</select>
<input type="submit" value="Get Authors names" name="Go" onClick="submitAddForm(this)">
<input type="button" value="Add" name="Add" onClick="setAuthorsNames()">
<br>
<br>
<input type="submit" value="Save Book" name="submitBook" onClick="submitAddForm()">
</form>
</body>
</html>

这是正在传递的参数。。

http://localhost:8082/OBL/BookServlet?longT=&shortT=&shortT=&dop=&nop=&noca=&Go=Get+Authors+names

您可以在提交表单之前使用隐藏输入元素并设置隐藏输入元素的值。

假设您的隐藏元素id为"hidden_input",然后在您的submitAddForm函数中添加以下行

document.getElementById("hidden_input").value = "desired_value";

现在,当表单提交时。。。隐藏的输入值将被设置并传递给服务器

您可以更改代码,并使用以下命令将参数从javascript传递给servlet:-

function submitAddForm(button) {

     var longT = document.getElementById("bookDetails").value;
     var shortT = document.getElementById("shortT").value;
     ...........
     ........... 
     then pass the variables and do 
     document.forms[0].action = "BookServlet?longT="+longT+"shortT="+shortT....and all the other variables to pass;     
     document.forms[0].submit();
}

在您的JSP中,您可以将"id"属性设置为:

长标题:<input type="text" name="longT" id="longT">