Javascript 添加验证以查看是否未选中单选按钮

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" />

以上代码对每个问题都重复，没有循环。i、 e.它是为每个问题编写的。但即使回答了所有问题，它仍然会显示“请回答问题1”

类似的内容

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

---

if（$（'input[type=radio]：checked'）。长度您应该使用逻辑运算符
&&
来处理您的情况

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) )

检查此项。您可以使用类似以下内容来代替验证每个元素

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;
       }
}

for（var i=1；i看起来您只使用了javascript。我建议您添加jQuery以简化javascript的编写

无论如何，只有使用javascript才能尝试以下操作：

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
}

var问题=30；
var-answer\u checked=假；
var one_not_checked=false；
对于（var i=1；i，此方法使用jQuery并检查一组答案中未选中的单选按钮

HTML-在问题中添加类

<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>

示例这里是您问题的答案。您也可以查看

仅使用此代码，我就为您的代码编写了此代码。请参见下文

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>

$("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.');
    }
});

下面的代码对于大人物来说更简单、更清晰

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

通过javascript访问

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;
}

你可以用这个：凯拉：谢谢你的回复。有没有一种方法，我可以给每个未回答的问题单独发出警告消息？？例如：如果第一个问题没有回答，提醒用户第一个问题需要回答等等。这是非常创新的，让用户知道确切的问题。我已经接受了你的建议answer@user2822187很高兴这对你有帮助.：）：）提供完整的问题而不仅仅是问题编号很好。这很有效，谢谢！！我可以把它放在循环中，这样我就不用写30个问题了？每个问题的名称属性命名为：问题1、问题2、问题3……等等
$("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.');
    }
});

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

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;
}