asked on

why undefined -?urgent

hi,

I have a checkbox like this:
<input type="checkbox" name="de" value="rs.getString("username") >
<input type=button value="Delete" onclick="Delete(this.form)">

..and javascript function is like this:

function Delete(theForm){

var id=theForm.de.value

pw = window.open("deleteuser.jsp?id="+id,"newProject",
"scrollbars=yes,status=no,resizable=yes,height=200,width=400");
pw.focus();

}

when i check the checbox and click Delete i get the value of id undefined, why is that, is there anything wrong with code.

Thanks

VincentPuglia

Hi,

Can't really say with code you posted, but the best guesses I can make, especially since you do not say where you get the error (before the window is opened or after):

var id=theForm.de.value

Since theForm is the form object, I have to presume that the problem lies in the variable name. place an alert after the assignment and see what you get:

var id=theForm.de.value
alert(id)

If that is where the error is, you need to change the name of the var 'id' to something like 'theID' since 'id' is probably being confused with the reserved word.

If none of the above helps, post some more code

Vinny

VincentPuglia

Hi,

You do have form tags around the checkboxes,right? And you are not getting the error from the popup? If you are, try appending 'opener.' to whatever code you are using to access the field.

Vinny

ho_alan

is that sth. u want?
undefine should be due to this.

<input type="checkbox" name="de" value="<%=rs.getString("username") %>">

shivsa

id is local thats why it come undefined.
try to make it global and see if it works.

Jasbir21

ASKER

sorry, just saw the input, pls give me a few minutes to read and then i would post the whole code..

thanks

VincentPuglia

shivsa: local or not makes no difference; the function has the form object, so it can grab the field value.

ho_alan: good catch

Vinny

Jasbir21

ASKER

hi,
when i put alert, i get undefined,

<SCRIPT LANGUAGE="JavaScript" TYPE="text/javascript">



</script>

the jsp part is

.....
<%
do

{
%>
<tr>
<td align=center class="data" ><input type="checkbox" name="de" value="<%=rs.getString("username")%>"></td>

<td align=center class="data" ><%=rs.getString("name")%></td>

<td align=center class="data" ><%= rs.getString( "username") %> </td>

<td align=center class="data" ><%= rs.getString( "skill") %> </td>

</tr>

<%
} while( rs.next() ) ;

}

%>

but if i were to try with drop down list, the value is not undefined.

thanks

VincentPuglia

hi,

where are the form tags? what does the rendered html look like?

="<%=rs.getString("username")%>"></td>
try putting single quotes around 'username' rather than double quotes

Vinny

Jasbir21

ASKER

hi,

<%@ page import="java.sql.*, com.dhal.*"%>

<html>
<head>

<title>Main Page</title>

<%
//***Declaration of variables...
String connectionURL = "jdbc:mysql://localhost:3306/mydatabase?user=;password=";
Connection connection = null;
Statement statement = null;
ResultSet rs=null;
String query="";
String user="";
String e="";
try
{

//***loading the jdbc driver...
Class.forName("com.mysql.jdbc.Driver").newInstance();
connection = DriverManager.getConnection(connectionURL, "", "");
statement=connection.createStatement();

}

catch( SQLException ex ) { ex.printStackTrace() ; }
catch( ClassNotFoundException ex ) {ex.printStackTrace() ;}

%>

<SCRIPT LANGUAGE="JavaScript" TYPE="text/javascript">



</script>
<style>



</style>
</head>
<body BGColor="#FFFFF0">

<form action="menuuser.jsp" name="form1">

</br>

<%

query="select * from volunteer order by name";
statement=connection.createStatement();
rs=statement.executeQuery(query);

if(rs.next()){

%>

<div style="overflow: auto; width: 60%; height: 300; padding:0px; margin-left:160px; ">
<table class="header" border="1" >
<tr>
<td align=center class="heading">
</td>

<td align=center class="heading">
Name
</td>

<td align=center class="heading">
Username
</td>

<td align=center class="heading">
Skill
</td>

</tr>

<%
do

{
%>
<tr>
<td align=center class="data" ><input type="checkbox" name="de" value="bad"></td>

<td align=center class="data" ><%=rs.getString("name")%></td>

<td align=center class="data" ><%= rs.getString( "username") %> </td>

<td align=center class="data" ><%= rs.getString( "skill") %> </td>

</tr>

<%
} while( rs.next() ) ;

}

%>

</table>
</div>

<%
//***To ensure all the database connections are close

try { if( rs != null ) rs.close(); rs=null ; } catch( Exception ex ) {ex.printStackTrace() ;}
try { if( statement != null ) statement.close() ; statement=null; } catch( Exception ex ) {ex.printStackTrace() ;}
try { if( connection != null ) connection.close() ; connection=null; } catch( Exception ex ) {ex.printStackTrace() ;}

%>

<input type=submit value="Delete" onclick="Delete(this.form)">

</form>
</body>
</html>

I try with value='hello'

still i get undefined, is there a difference in assigning value to of type of checkbox, i mean if input type
<input type="text ..value='yy'>
but checkbox is there any difference.

thanks

ho_alan

Vinny is correct :-)

if you want to relate the <input> stuff form in JS functions
u have to embed it with <form name=theForm> and </form>

ho_alan

try to add "return true" at the end of the JS function

JakobA

on this line:
<input type="checkbox" name="de" value="rs.getString("username") >
it looks like you are mixing asp code and javascript code. That is no good.

if I am correct in thinking that rs.getString("username") should be performed by javascript, the line should be:

<input type="checkbox" name="de" value="<% =rs.getString("username") %>">

regards JakobA

JakobA

Oops: 'performed by javascript' should be 'performed by ASP'

ho_alan

there should be no difference for getting the value
<input type=text> and <input type=checkbox>
check lower and upper case

Jakob : your point (<%=xxxxxx %>) is already spotted out in the comments before :-)

Jasbir21

ASKER

hi,
i tried ,thanks.

I mean i did try to put explicitly value='bad', meaning the value is bad and

value='good', meaning value is good,

but it still seem to work,

i mean it seems like the input value is not getting anything

thanks

JakobA

>> ho_alan >> you are right, I had missed your earlier post. sorry

JakobA

html forms only send a name=value pair for checkboxes that are checked, for uncehcked checkboxes you recieve nothing.

Jasbir21

ASKER

..i think i get it, that's why it works with drop down list and not checkbox, but lets say i still need the checkbox,

I mean when the menuuser.jsp appears, the checkbox is not be checked.

But when the user check the checkbox, the id needs to be sent,how is that then..

I mean what do i need to do not to get undefined then

thanks

SOLUTION

ho_alan

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Jasbir21

ASKER

hi,

this is what i did:

function Delete(theForm){
if(!theForm.po.checked){

alert(theForm.po.value);
return true;
}

}

Surprisingly, the alert did pop up with undefined even when i checked the box, what do i do, i really don't know what to do ..

ASKER CERTIFIED SOLUTION

etain

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Jasbir21

ASKER

hi,
thanks it helps ..how to change it so that only one box can be checked because i need to send one id,

Jasbir21

ASKER

i mean if there is for example 10 checkbox, a user click one ,

thanks

etain

if u want to be simple just change checkbox to radio

etain

using checkbox add this function

function Select(sobj)
{
     if (sobj.checked)
      {
            var obj = findObj("de")
            if (obj != null)
            {
                 if (obj.length > 1 )
                  {
                        for (c=0; c < obj.length;c ++)
                        {
                              if(findObj("de")[c] != sobj ) findObj("de")[c].checked = false
                        }
                  }
            }
      }
}
</script>
<body>
<input type="checkbox" id ="de" name="de" value="1" onClick="Select(this)">
<input type="checkbox" id ="de" name="de" value="2" onClick="Select(this)">
<input type="checkbox" id ="de" name="de" value="3" onClick="Select(this)">
<input type=button value="Delete" onClick="Delete()">
</body>

Jasbir21

ASKER

hi,
I think you are right, actually i want to use checkbox that allows me to send few id, actually i need some changes on the same code,

I am closing this question and posting a new one.Pls look at the link that i would place.
Etain, the modications are on your code.Could you pls see the link.
I have asked a lot here.

I would like to thank everyone for helping me..

thanks

Jasbir21

ASKER

The modification for the code:
is at the link

https://www.experts-exchange.com/questions/20807928/Checkbox-Modification-on-Code.html

thanks

JakobA

>> etain >>
in your example of Date: 11/25/2003 12:47AM PST you have several checkboxes with the same name and id. this is naughty. identical name values are used only for grouping radio buttons. id-values should never be identical.

etain

>>JakobA>>
In HTML, if id is identical it become array.
There is no rule saying that u cant group HTML element, other then radio buttons