我必须使用以下代码的javascript验证单选按钮的表单

Question

i have retrieve questions and answers from the sql table and represented them using this code. now, i have a problem that how to take the radio button name in javascript. for every question there must be a one option checked. i have to do this for all questions.

<form action="answer.php?title=<?php echo $_GET['title'];?>" method="post">
<table id="myques"> 
<?php 
$i=0;
while($row=mysql_fetch_array($result)){
?>     
<tr>
<td><?php echo ++$i.')'; ?></td>
<td>&nbsp&nbsp&nbsp<?php echo $row['question']; ?></td>
</tr>
<tr>
<td></td>
<td><input type="radio" name="<?php echo $row['question'];?>" id="ques" value="<?php echo $row['opt1'];?>"><?php echo $row['opt1']; ?></td>
</tr>
<tr>
<td></td>    
<td><input type="radio" name="<?php echo $row['question'];?>" id="ques" value="<?php echo $row['opt2'];?>"><?php echo $row['opt2']; ?></td>
</tr>
<tr>
<td></td>    
<td><input type="radio" name="<?php echo $row['question'];?>" id="ques" value="<?php echo $row['opt3'];?>"><?php echo $row['opt3']; ?></td>
</tr> 
<tr>
<td></td>    
<td><input type="radio" name="<?php echo $row['question'];?>" id="ques" value="<?php echo $row['opt4'];?>"><?php echo $row['opt4']; ?></td>
</tr>
<?php } ?>       
<tr><td colspan="4"><input type="submit" name="add" onClick="return validate()" /></td></tr>         
</table>

Answer 1

Try this:

<input type="radio" name="question" id="ques" value="1">
<input type="radio" name="question2" id="ques2" value="2">
<input type="radio" name="question3" id="ques3" value="3">

Or you decide on names make sure they are different..

And for JS:

var projectObj = document.form1.project
var len = projectObj.length
var chosen = null;

for (i = 0; i <len; i++) {
    if (projectObj[i].checked) {
       chosen = projectObj[i].value
    }
}

if (chosen == null) {
    alert("No Radio Button Chosen")
}

SOURCE CREDIT GIVEN TO : How to check if one of radio buttons was selected?

Answer 2

There is no easy way to do this. Or you can use default checked option in your HTML. I think it will be conflict with your business. In your JS:

// store your question names in JS array
// check them  group by group. and it will give detail information for which question is not check.

OR In your JS:

// I think there will be four option answers in one question.
// count the total number of questions. and make the radion id as "radion1","radion2"...
// for all radios, if the checked number is equals with the question, the form submit is valid.

Answer 3

<td><input type="radio" name="<?php echo $row['question'];?>" id="ques<?=$i?>" value="<?php echo $row['opt1'];?>" checked="true"><?php echo $row['opt1']; ?></td>

这就是您想要的吗？只需在第一个选项中添加checked =“ true”，然后您就可以做到。