Develop Reference

my dynamically populated radio button group gets more than one item checked. so how to solve this.?using HTML,CSS,JS; C#(backend)

my dynamically populated radio button group gets more than one item checked. so how to solve this.?using HTML,CSS,JS; C#(backend).
i wrote a code for list of items with input type as "radio". the values of list item is stored in a Arraylist in backend i.e C#. but when i try to run the code, more than one radio button gets selected.
please help me solve my issue. and even how to check which radio value is selected and how to pass the checked radio value to backend or server.
HTML code
<div class="demo-container size-thin">
<div class="RadListBox RadListBox_Silk" >
<div class="rlbGroup">
<ul>
<%
foreach (var item in dataname)
{
%>
<li>
<input type="radio" />
<img alt="" src="Images/<%=item %>.png"> <%= item%></li>
<%
}
%>
</ul>
</div>
</div>
</div>
Sample frontend visual
i have not writeen any javascript code as of now.

To be clearer than the other answers. All radio buttons in a group must have identical values for their name attribute. This is what groups them together. It's their value attribute that is used to give each button its individual meaning.
Additionally, the name attribute is necessary for any/all form elements that are supposed to submit their value during the submit event. If an element doesn't have the name attribute, it won't send its data.
Once you've made this change, you don't have to worry about how to send the checked radio button's value to the backend server because that will be done automatically when the form that the radio button is in gets submitted.
// Get reference to parent element of first radio button group
var parent = document.querySelector("fieldset:first-child");
// Set up click event handler for it
parent.addEventListener("click", function(e){
// Check to see if the originator of the event was a radio button
if(e.target.nodeName === "INPUT" && e.target.getAttribute("type") === "radio"){
// Get a reference to the checked radio button
console.log("Checked radio button is: " +
document.querySelector("input[type=radio][name=testGroup1]:checked").value);
}
});
<fieldset>
<legend>Group 1</legend>
<label> Choice A<input type="radio" name="testGroup1" value="A"></label><br>
<label> Choice B<input type="radio" name="testGroup1" value="B"></label><br>
<label> Choice C<input type="radio" name="testGroup1" value="C"></label>
</fieldset>
<fieldset>
<legend>Group 2</legend>
<label> Choice A<input type="radio" name="testGroup2" value="A"></label><br>
<label> Choice B<input type="radio" name="testGroup2" value="B"></label><br>
<label> Choice C<input type="radio" name="testGroup2" value="C"></label>
</fieldset>

You need to give a name to it
<input type="radio" name="myRadio">
this way the radio know which "group" is it from
input radio

#Sourav,
First, we've to set the name of that radio button.
<input type="radio" name="nameOfThisField">

Get value of radio button group in route after form submit?

I have a radio button group on my page which is within a form. When the form is submitted, I would like to retrieve the values of the form and save them to my database. It seems that the value for the radio button group is radiobtngrp: 'on' but I don't know which one of the radio buttons is on. How do radio buttons work on the submit of a form?
Here is my HTML code for the radio buttons:
<label for="q-<%= question.id %>">
<input id="q-<%= question.id %>-r-i" type="radio" class="form-control" name="radiobtn">
<img src="/images/a.png">
</label>
I have multiple radio buttons which are added through a loop in my ejs file.
My submit button looks like this:
<button class="btn btn-lg btn-signin btn-yellow" type="submit">Submit</button>
Now in my route, if I try something like this:
console.log(req.body.radiobtn);
I see this in the console:
radiobtn: 'on'
Why is this? And how can I get the actual radio button which was clicked?
Thanks in advance!

Give each radio button in a group both name and value attributes.
The name attribute value is used as the key when submitting a form, with the value of the key taken from the value attribute of the selected radio button.
All buttons in the same group share the same name attribute value.
Here a quick HTML demo: it's not supposed to do anything except show the query string in the location bar when you hit submit:
<form method="get">
<input type="radio" name="myRadio" value="1">( value 1)<br>
<input type="radio" name="myRadio" value="2">( value 2)<br>
<input type="radio" name="myRadio" value="3">( value 3)<br>
<input type="submit" value="submit">
</form>
The default value of the value attribute is the string "on". Hence "on" is sent as the value of the radio group named "radiobtn" when the selected button is missing a value attribute. (Ref. HTML standard)

check box validation before clicking proceed button

Proceed </button>
<input type="checkbox" name="checkbox3" value="yes">
By checking the box, I certify that have read the above disclaimers and agree to the rules. </input>
I have a checkbox and a button which will take me to next page. But, before I press the button the check box has to be ticked. If not, a label has to be displayed below the check box saying "accept to rules first". Help? Also, it would be great if i can highlight the checkbox to red if i click proceed without checking the checkbox. Can use javascript/jquery.

Try this it works
<form action="page.html">
<input type="checkbox" name="checkbox3" value="yes" required>
By checking the box, I certify that have read the above disclaimers and agree to the rules. </input>
<input type="submit" name ="submit"/>
</form>

To get you started:
<input id="checkboxAgree" type="checkbox" name="checkbox3" value="yes">
function checkAgree()
{
if (document.getElementbyId("checkboxAgree").getAttribute("checked") )//checkbox is checked
{
location.href = "page.html"; //load the next page.
}
else
{
Alert("You need to check the box before you can continue");
}
}
document.getElementById("proceed-button").addEventListener("click", checkAgree ,false);
addEventListener add an onclick event to the button. When clicked this executes the function checkAgree. When the checkbox has the attribute checked it is checked and the ifwill render true. location.href will load page.html.
Please delete the a that surrounds your button.

selecting radio options doesnt change checked attribute

I am generating an HTML form with some radio buttons and checkboxes. the generated code for the radio buttons for instance are like these:
<input id="101_2" type="radio" name="101" value="2" >
<input id="101_3" type="radio" name="101" value="3" checked="true">
Using JavaScript I can make a for cycle to see what radio is checked using the check attribute.
The problem is that if I manually click in another radio option (from the same group as in the example), visually in the HTML I can see that another radio is selected, but the JavaScript is still saying that the input 101_3 is the selected radio option. If I look at the HTML using firebug I can see that the new selected option is indeed not selected (doesn't have the checked attribute)... despite I have selected manually.
Any ideas on this?

Fist and formost when naming your radio buttons or any type of DOM input element never start the name of an input element with a number, always start the name of your input element with a letter.
For your posted code you would name your radios in similar fashion, one01 or x101 or o101,ect...
Do the same thing with your ids' of any DOM element. Never start an id of a DOM element with a number.
--HTML
<input id="x101_2" type="radio" name="x101" value="2">
<input id="x101_3" type="radio" name="x101" value="3" checked="checked">
<br /><br />
<button type="button" onclick="WhatsChecked()">Whats Checked?</button>
--JavaScript
function WhatsChecked() {
var radCk = document.body.querySelectorAll('input[name="x101"]:checked')[0];
alert(radCk.id);
};
--Fiddler
fiddler

radio buttons + input field for one of them

I tried the following but it returns two pieces of data to the server. This is a problem for my gateway, and I get an error.
I used this for one of my attempts:
<script type="text/javascript">
if( $('#other).is('):selected') )
{
// user wants to enter own value
$('[name="installments"]").not('[type="text"]').attr('name', '') // remove all
values apart from the entered text.
}
</script>
<body>
<FORM ACTION="http://www.cs.tut.fi/cgi-bin/run/~jkorpela/echo.cgi" METHOD="POST">
<br><br>
<input type="radio" name="installments" id="r1" checked="checked" value="99">
Open-Ended - I can stop them via email at any time.<br>
<label for="installments">number of payments</label><br>
<input type="radio" name="installments" id="other" value="Enter Custom.."><br>
<input type="text" name="installments" value="" maxlength="4" size="4">
<br><br><br>
<input type="submit" name="btnSubmit" value="Submit" />
</form>
This returns either -
installments 99
installments (empty)
or
installments Enter Custom..
installments 5
I can only have one return for the var 'installments' either 99 or the number they imputed.
I have tried various ways of doing this using JS and allowing the user to make a choice with the same results - two instances of the var 'installments' being sent.
Is there a javascript way to test the input field and if a number is entered then disable using id(s) the extra radio button so it can't send any data? Or is there a better way to do this?
Solved
I found the answer & Here it is
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script type="text/javascript">
$(function() {
$('#user_input').change(function() {
$('#use_user_input').val($(this).val());
});
});
</script>
And Html Here:
Total number of payments...</span><br>
<input type="radio" name="installments" checked value="99">
Open-Ended -
<input id="use_user_input" type="radio" name="installments" value="">
limited number of payments -
<input id="user_input" type="text" value="" maxlength="4" size="4"></span>

You would want to give the input text field a different name from the radio inputs, then handle the text field's POST as a separate variable from the radio buttons in the HTTP request. Also, give the second radio input a value, such as "other" so you know to handle the associated text input.

If you only have the ability to receive one field from the form you will need to alter the form as the user fills it in. Currently the form works if the user selects one of the values delimited by the radio buttons. The problem, I gather, is that the status of the radio buttons overrides the value of the text field even if the user selects the "other" option of filling in the text box.
The solution is to use a script that is triggered when the user changes the content of the text box. This script will read the value of the text box and assign that value to the 'other' radio button.
We can do this using the onchange event:
<input id="otherRadio" type="radio" name="installments" value="" /><br />
<input id="otherText" type="text" value="" maxlength="4" size="4" onchange="applyOtherOption()" />
If you try this now, it will cause a javascript error on your page when you change the value of the the text field. This is because the browser fails to find a javascript function with the name applyOtherOption. Let's change that now:
<script type="text/javascript">
function applyOtherOption() {
var textField = document.getElementById("otherText");
var radioField = document.getElementById("otherRadio");
radioField.value = textField.value;
}
</script>
The result is that the "other" radio button's value is always changed to whatever the user enters into the text field and if this radio is selected, this is what is sent with the form.
Important
I've been a bit lazy here and typed out the easiest way to access the content of the form elements. This will work on most (probably all major) browsers but it is not the way it should be done. The proper method is to access the form first, then from the form element access the fields. To do it right you should read this article on setting the value of form elements.
I hope this is useful.