Send values from jsp to Servlet

Question

i have a jsp in which i have select tag and i want to get the and the value selected from the select in jsp in my Servlet

<select id="listoffood" name="dropdown" onchange="foodname();">
<option value="bg">Burger</option>
<option value="pas">pasta</option>
<option value="pi">pizza</option>
</select>
<div id='content'></div>

here is the javascript code

function foodname()
{

  var xmlHttpReq = false;
    var self = this;
    document.getElementById('content').innerHtml='';
    // Mozilla/Safari
    if (window.XMLHttpRequest) {
        self.xmlHttpReq = new XMLHttpRequest();
    }
    // IE
    else if (window.ActiveXObject) {
        self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
    }

    self.xmlHttpReq.open('GET', "InformationServlet", true);
    self.xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    self.xmlHttpReq.send(null);

    self.xmlHttpReq.onreadystatechange= function ()
    {
        //alert(document.getElementById('content'));
        if (self.xmlHttpReq.readyState==4)
        {
        if (self.xmlHttpReq.status == 200)
        {

        document.getElementById('content').innerHTML=self.xmlHttpReq.responseText;
        }
        }
    };

}

What i have done is used a get Attribute like this but it aint working its showing null

protected void doGet(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException 

    {
    // TODO Auto-generated method stub

    String coun = request.getParameter("dropdown");
    PrintWriter out=response.getWriter();
    System.out.println("here : "+coun);
}

Thanks in advance and any piece of code is highly appreciated.

what does method foodName() do? Is your select inside form? — Kshitij
– Kshitij, Commented May 3, 2013 at 10:50
#kshitj food name goes to javascript and js than calls servlet by ajax. @Baadshah yes it goes to same servlet on onChange method — Anish Sharma
– Anish Sharma, Commented May 3, 2013 at 10:52
Are you able to get other parameters from this JSP page in your servlet ? — Ankit Singla
– Ankit Singla, Commented May 3, 2013 at 10:58
i dnt have any html form i just have a select tag on my jsp @AnkitSingla i dont have ant other parameters on my jsp its jusst the select tag — Anish Sharma
– Anish Sharma, Commented May 3, 2013 at 10:59

Ravi K Thapliyal · Accepted Answer · 2013-05-03 12:29:09Z

1

Just change your AJAX open() request as

var select = document.getElementById("listoffood");
self.xmlHttpReq.open('GET', "InformationServlet?dropdown=" + select.options[select.selectedIndex].value, true);

edited May 3, 2013 at 12:29

answered May 3, 2013 at 11:49

Ravi K Thapliyal

51.8k9 gold badges80 silver badges90 bronze badges

Sign up to request clarification or add additional context in comments.

8 Comments

Anish Sharma Over a year ago

its localhost:8080/Distributor/InformationServlet and its showing an error in the code u gave.. the error is cannot read property 'undefined' of undefined

Anish Sharma Over a year ago

nothing is wrong with the url its showing errror in js.. i have mentioned the error in my previous comment

Ravi K Thapliyal Over a year ago

@AnishSharma Did you try with var select.

Anish Sharma Over a year ago

yes i did it than shows cannot read property "options" of the undefined

Ravi K Thapliyal Over a year ago

@AnishSharma I just tested the code and successfully did a GET for http://www.google.com/search?q=pasta. Can you do an alert(document.getElementById("listoffood")); As per your HTML this shouldn't be undefined. Please verify. (two "f"s here)

|

Ilya · Accepted Answer · 2013-05-03 11:00:33Z

0

Use method getParameterValues(String).
This is because <select> tag can have multiple selected values (e.g. select multiple)

String[] coun = request.getParameterValues("dropdown");

answered May 3, 2013 at 11:00

Ilya

29.9k19 gold badges119 silver badges161 bronze badges

1 Comment

Ravi K Thapliyal Over a year ago

I knew somebody will post this. multiple is not true for select.

Community · Accepted Answer · 2017-05-23 12:28:09Z

0

Check this post:

How to use onClick() or onSelect() on option tag in a JSP page?

You seems to be using select tag without any action such as onchange

edited May 23, 2017 at 12:28

CommunityBot

11 silver badge

answered May 3, 2013 at 11:01

Juned Ahsan

68.8k12 gold badges101 silver badges138 bronze badges

2 Comments

Ravi K Thapliyal Over a year ago

onchange=foodname(); I think you missed seeing that!

Ravi K Thapliyal Over a year ago

@AnishSharma Using a event handler on select is fairly common and not the problem here. You don't need to change that.

Ankit Singla · Accepted Answer · 2013-05-03 11:03:43Z

0

You can get selected item text from list box using

var e = document.getElementById("dropdown");
var selectedValue = e.options[selectBox.selectedIndex].value

in your JS method and send this value with servlet's link.

answered May 3, 2013 at 11:03

Ankit Singla

1982 silver badges15 bronze badges

5 Comments

Anish Sharma Over a year ago

how can i send the value with servlet link

Ankit Singla Over a year ago

InformationServlet?dropdown=selectedValue And use request.getParameter("dropdown"); in your servlet as you have already done.

Anish Sharma Over a year ago

<display-name>Distributor</display-name> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <servlet> <servlet-name>InformationServlet</servlet-name> <servlet-class>requestData.InformationServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>InformationServlet</servlet-name> <url-pattern>/InformationServlet</url-pattern> </servlet-mapping> </web-app>

Ravi K Thapliyal Over a year ago

@AnishSharma Did you check my answer?

Ankit Singla Over a year ago

@AnishSharma : Have you given the correct package path for <servlet-class> parameter ??

NPKR · Accepted Answer · 2013-05-03 11:23:04Z

get the value from select tag

var e = document.getElementById("dropdown");
var selectedValue = e.options[selectBox.selectedIndex].value;

and edit js function

self.xmlHttpReq.open('GET', "InformationServlet?dropdown="selectedValue , true);

finally your should looks like

function foodname()
{

    var e = document.getElementById("dropdown");
    var selectedValue = e.options[selectBox.selectedIndex].value;

  var xmlHttpReq = false;
    var self = this;
    document.getElementById('content').innerHtml='';
    // Mozilla/Safari
    if (window.XMLHttpRequest) {
        self.xmlHttpReq = new XMLHttpRequest();
    }
    // IE
    else if (window.ActiveXObject) {
        self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
    }

    self.xmlHttpReq.open('GET', "InformationServlet?dropdown="selectedValue , true);
    self.xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    self.xmlHttpReq.send(null);

    self.xmlHttpReq.onreadystatechange= function ()
    {
        //alert(document.getElementById('content'));
        if (self.xmlHttpReq.readyState==4)
        {
        if (self.xmlHttpReq.status == 200)
        {

        document.getElementById('content').innerHTML=self.xmlHttpReq.responseText;
        }
        }
    };
}

Collectives™ on Stack Overflow

Send values from jsp to Servlet

5 Answers 5

8 Comments

1 Comment

2 Comments

5 Comments

1 Comment

Linked

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

8 Comments

1 Comment

2 Comments

5 Comments

1 Comment

Linked

Related