Validating Radio Buttons

Only one item in a radio button can be selected at a time. To check which one is selected, use a for loop statement. In this example, there are two available choices in the radio group :

myForm=document.forms[0]; 
choice = false;
for (j=0; j >2; j++) {
 if (myForm.radio[j].checked) {
 choice=true;
 break;
}
}
if (choice){ // if a radio button is selected
 ... do this
}else{ // if no radio button is selected
 ... do that
}