validate <input type="radio">

[Zayn]

I'm working on an assignment for school where we're working with JavaScript (I'm only allowed to use JavaScript) to validate a form for a payment page. It's my first time working with JavaScript so and I feel a bit lost..i need to link htmp radio buttons and javascript with a Calculate button


thml code

<td><input type="text" id="text7" name="fexpirydate" placeholder="22/08/2030" maxlength="30">
        <tr/>
        <tr>
        <td><input type="radio" name="gender" value="Cash" checked><strong>Cash</strong></td>
        </tr>
        <tr>
        <td><input type="radio" name="gender" value="Ecocash" checked><strong>Ecocash</strong></td>
        </tr>
        <tr>
        <td><input type="radio" name="gender" value="Swipe" checked><strong>Swipe</strong></td>
        </tr><br><br><br>

[gits]

what exactly should happen in the program here and what have you done so far to solve it?

[parth123]

<form name="form1" action="#" onsubmit="return validateForm()" method="post"> 
    First time visitor?:<br/>
            <label for="s1">Yes</label>
            <input type="radio" id="radio1" name="yesno" value="1"/>
            <br/>
            <label for="s2">No</label>
            <input type="radio" id="radio2" name="yesno" value="2"/>
 
            <br/>       
 
    <input type="submit" value="Submit"><br/>
    </form>
 

function validateForm() {
    var radios = document.getElementsByName("yesno");
    var formValid = false;
 
    var i = 0;
    while (!formValid && i < radios.length) {
        if (radios[i].checked) formValid = true;
        i++;        
    }
 
    if (!formValid) alert("Must check some option!");
    return formValid;
}

[gits]

throwing out some code without knowing what the exact problem is is plain guesswork. While the OP is already asking because he/she is lost - with no further elaboration of that shown code it probably even wont help much - the answer could even be 42.

Besides that its pretty sub-optimal to do validations like that - since it requires DOM operations. its much more optimal when using events to update a state - you will see that when you have pages with lots of elements that you are validating the way you propose here.