javascript - 添加验证以查看是否未选择单选按钮

Question

我有以下代码：

 <li>1. question 1</li>
<li>
     <input type="radio" name="question1" id="sd1" value="1">Strongly Disagree
     <input type="radio" name="question1" id="d1" value="2">Disagree
     <input type="radio" name="question1" id="n1" value="3">Neither Agree Nor Disagree
    <input type="radio" name="question1" id="a1" value="4">Agree
     <input type="radio" name="question1" id="sa1" value="5">Strongly Agree
</li>
<br/><br/>

<li>2.  question 2 </li>
<li>
     <input type="radio" name="question2" id="sd2" value="1">Strongly Disagree
     <input type="radio" name="question2" id="d2" value="2">Disagree
     <input type="radio" name="question2" id="n2" value="3">Neither Agree Nor Disagree
    <input type="radio" name="question2" id="a2" value="4">Agree
     <input type="radio" name="question2" id="sa2" value="5">Strongly Agree
</li>
<br/><br/>

<li>3.  question 3</li>
<li>
     <input type="radio" name="question3" id="sd3" value="1">Strongly Disagree
     <input type="radio" name="question3" id="d3" value="2">Disagree
     <input type="radio" name="question3" id="n3" value="3">Neither Agree Nor Disagree
     <input type="radio" name="question3" id="a3" value="4">Agree
     <input type="radio" name="question3" id="sa3" value="5">Strongly Agree
</li>
<br/><br/>

  <input type="submit" value="Submit" name="Submit" id="Submit" />

我有这样的30个问题。我的要求是用户必须回答所有 30 个问题。

我如何编写 javascript 函数，以便在用户甚至没有回答其中一个问题时向他显示一条消息。编辑：

我的javascript的问题是：

   if ( (thisfrm.question3[0].checked == false) || (thisfrm.question3[1].checked == false) || (thisfrm.question3[2].checked == false) || (thisfrm.question3[3].checked == false) || (thisfrm.question3[4].checked == false))
{
    alert('Please answer question 1');
    return false;
}

对于每个没有循环的问题，都会重复上面的代码。即它是为每个问题编写的。但即使所有问题都已回答，它仍然显示请回答问题 1

score 7 · Accepted Answer

此方法利用 jQuery 并检查一组答案中未选中的单选按钮

HTML - 为您的问题添加一个类<li>

<li>1. question 1</li>
<li class="option">
     <input type="radio" name="question1" id="sd1" value="1">Strongly Disagree
     <input type="radio" name="question1" id="d1" value="2">Disagree
     <input type="radio" name="question1" id="n1" value="3">Neither Agree Nor Disagree
     <input type="radio" name="question1" id="a1" value="4">Agree
     <input type="radio" name="question1" id="sa1" value="5">Strongly Agree
</li>

Javascript

// Delegate submit action
$(document).on('submit', 'form', function () {

    var validate = true;
    var unanswered = new Array();

    // Loop through available sets
    $('.option').each(function () {
        // Question text
        var question = $(this).prev();
        // Validate
        if (!$(this).find('input').is(':checked')) {
            // Didn't validate ... dispaly alert or do something
            unanswered.push(question.text());
            question.css('color', 'red'); // Highlight unanswered question
            validate = false;
        }
    });

    if (unanswered.length > 0) {
        msg = "Please answer the following questions:\n" + unanswered.join('\n'); 
        alert(msg);
    }
    return validate;
});

这里的例子http://fiddle.jshell.net/6jNpQ/2/

score 6 · Accepted Answer

下面的代码对于大人物来说更加简单和干净

if (!$("input[name='html_elements']:checked").val()) {
   alert('Nothing is checked!');
}
else {
  alert('One of the radio buttons is checked!');
}

看看下面的小提琴演示

访问http://jsfiddle.net/creators_guru/DBd79/

score 2 · Accepted Answer

检查这个。您可以使用类似这样的东西，而不是验证每个元素

for(var i = 1 ; i <= 30 ; i++)
  {
      var radios = document.getElementsByName('question'+i);
      var checked = false;
      for (var j = 0, length = radios.length; j < length; j++) 
      {

         if (radios[j].checked) 
         {
          checked = true;
          break;
         }


       }
       if(!checked)
       {
         alert('Please answer question '+i);
         break;
       }
}

score 1 · Accepted Answer

看起来您只使用 javascript。我建议您添加 jQuery 以使编写 javascript 更容易。

无论如何，只有使用 javascript 你可以试试这个：

var questions = 30;
var answer_checked = false;
var one_not_checked = false;
for (var i = 1; i <= questions; i++) {
    for (var j=0; j < document.getElementsByName('question'+i).length; j++) {
        answer_checked = answer_checked || (thisfrm['question'+i][j].checked == true);
    }
    one_not_checked = one_not_checked || !answer_checked;
    answer_checked = false;
}

if (one_not_checked) {
    // your message to the user as one answer is not checked
}

score 0 · Accepted Answer

&&您应该为您的条件使用逻辑运算符

if ( (thisfrm.question3[0].checked == false) && 
     (thisfrm.question3[1].checked == false) && 
     (thisfrm.question3[2].checked == false) && 
     (thisfrm.question3[3].checked == false) && 
     (thisfrm.question3[4].checked == false) )

score 0 · Accepted Answer

像这样的东西？

if ($('input[type=radio]:checked').length <= 0) {
    alert("No radio checked")
}

还是按名字做？

if ($('input[name=question1]:checked').length <= 0) {
    alert("No radio checked")
}

score 0 · Accepted Answer

这是您问题的答案。你也可以检查一下。

只需使用此代码，我就为您的代码编写了它。请看下面

HTML 代码

<form method="POST" action="/echo/html/?html=;delay=3;">
    <ul>
        <li class="question">1) question 1</li>
        <li class="answers">
            <input type="radio" name="question1" id="11" value="1" />Strongly Disagree
            <input type="radio" name="question1" id="12" value="2" />Disagree
            <input type="radio" name="question1" id="13" value="3" />Neither Agree Nor Disagree
            <input type="radio" name="question1" id="14" value="4" />Agree
            <input type="radio" name="question1" id="15" value="5" />Strongly Agree
        </li>

        <li class="question">2) question 2</li>
        <li class="answers">
            <input type="radio" name="question2" id="21" value="1" />Strongly Disagree
            <input type="radio" name="question2" id="22" value="2" />Disagree
            <input type="radio" name="question2" id="23" value="3" />Neither Agree Nor Disagree
            <input type="radio" name="question2" id="24" value="4" />Agree
            <input type="radio" name="question2" id="25" value="5" />Strongly Agree
        </li>

        <li class="question">3) question 3</li>
        <li class="answers">
            <input type="radio" name="question3" id="31" value="1" />Strongly Disagree
            <input type="radio" name="question3" id="32" value="2" />Disagree
            <input type="radio" name="question3" id="33" value="3" />Neither Agree Nor Disagree
            <input type="radio" name="question3" id="34" value="4" />Agree
            <input type="radio" name="question3" id="35" value="5" />Strongly Agree
        </li>
    </ul>
    <input type="submit" value="Submit" name="Submit" id="Submit" /> 
</form>

Javascript代码

$("form").submit(function () {
    var allChecked = true;
    $('li.answers').each(function () {
        if (!$(':radio', this).is(':checked')) {
            allChecked = false;
            return false;
        }
    });
    if (!allChecked) {
        alert('Please fill the form completely...');
        return false;
    } else {
        alert('You have filled the complete form.');
    }
});

score 0 · Accepted Answer

#通过 javascript

function validate(){
if (checkRadio("question1") && checkRadio("question2") && checkRadio("question3")){
 return true;
}else{
alert("Please answer all Questions!");
 return false;
}
}
function checkRadio(name){
 var radio = document.forms.myForm[name];
for (var option in radio){
if(radio[option].checked){
 return true;
}
}
return false;
}

javascript - 添加验证以查看是否未选择单选按钮

8 回答 8

Related

Reference