javascript - Show error message when <select> is emptyno selection or default - Stack Overflow

I'm trying to get an error message when select is set to default and nothing is selected. For inpu

I'm trying to get an error message when select is set to default and nothing is selected. For input fields the code works, but I can't figure out where I'm wrong for the select part. Anyone help me?

Fiddle: /

//Error Msg for input field
function validateForm() {
  let x = document.forms["myForm"]["fname"].value;
  if (x == "") {
alert("Name must be filled out");
return false;
  }
}
<input type="text" name="fname" form="myForm">
<select id="select-sex" form="myForm" name="radios"> 
 <option id="opt-default" form="myForm" selected>Select...</option>
 <option id="sexuomo" name="radios" value="Male" form="myForm">Uomo</option>
 <option id="sexdonna" name="radios" value="Female" form="myForm">Donna</option>
</select>


<button onclick="validateForm()">Submit</button>
<form name="myForm" id="myForm" onsubmit="return validateForm()" method="post">
</form>

I'm trying to get an error message when select is set to default and nothing is selected. For input fields the code works, but I can't figure out where I'm wrong for the select part. Anyone help me?

Fiddle: https://jsfiddle/snake93/1sLtk2a7/2/

//Error Msg for input field
function validateForm() {
  let x = document.forms["myForm"]["fname"].value;
  if (x == "") {
alert("Name must be filled out");
return false;
  }
}
<input type="text" name="fname" form="myForm">
<select id="select-sex" form="myForm" name="radios"> 
 <option id="opt-default" form="myForm" selected>Select...</option>
 <option id="sexuomo" name="radios" value="Male" form="myForm">Uomo</option>
 <option id="sexdonna" name="radios" value="Female" form="myForm">Donna</option>
</select>


<button onclick="validateForm()">Submit</button>
<form name="myForm" id="myForm" onsubmit="return validateForm()" method="post">
</form>

Share Improve this question asked Oct 9, 2021 at 16:05 Snake93Snake93 4765 silver badges22 bronze badges 1
  • document.querySelector('#select-sex').value == 'Select...' will retrn true if its not filled out – doo_doo_fart_man Commented Oct 9, 2021 at 16:10
Add a ment  | 

2 Answers 2

Reset to default 2

Just repeat your logic you used on the input for the select:

//Error Msg for input field
function validateForm() {
  let x = document.forms["myForm"]["fname"].value;
  if (x == "") {
    alert("Name must be filled out");
    return false;
  }
  let y = document.forms["myForm"]["radios"].value;
  if (y == "Select...") {
    alert("Select must be filled out");
    return false;
  }
}
<input type="text" name="fname" form="myForm">
<select id="select-sex" form="myForm" name="radios">
  <option id="opt-default" form="myForm" selected>Select...</option>
  <option id="sexuomo" name="radios" value="Male" form="myForm">Uomo</option>
  <option id="sexdonna" name="radios" value="Female" form="myForm">Donna</option>
</select>


<button onclick="validateForm()">Submit</button>
<form name="myForm" id="myForm" onsubmit="return validateForm()" method="post">
</form>

However, a much more scalable solution is to add the required field to your inputs, then use checkValidity():

function validateForm(){
  const isValid = myForm.checkValidity();
  if(!isValid){
    alert("Please fill all fields");
  }
  return isValid;
}
<form name="myForm" id="myForm" onsubmit="return validateForm()" method="post" novalidate>
  <input type="text" name="fname" form="myForm" required>
  <select id="select-sex" form="myForm" name="radios" required>
    <option id="opt-default" value="" form="myForm" selected disabled>Select...</option>
    <option id="sexuomo" name="radios" value="Male" form="myForm">Uomo</option>
    <option id="sexdonna" name="radios" value="Female" form="myForm">Donna</option>
  </select>
  <button>Submit</button>
</form>

An <option> without a value= defaults to the text value of that option. ie

<option>Seleziona</option>

is the same as

<option value="Seleziona">Seleziona</option>

So you either need to check for "Seleziona" or you need to give it a value.

<option value="">Seleziona</option>

Note: Seleziona es from OPs fiddle

Updated snippet:

//Error Msg for input field
function validateForm() {
  let name = document.forms["myForm"]["fname"].value;
  let gender = document.forms["myForm"]["radios"].value;
  if (name == "" || gender == "") {
    alert("Name and gender must be filled out");
    return false;
  }
}
<input type="text" name="fname" form="myForm">
<select id="select-sex" form="myForm" name="radios">
  <option id="opt-default" form="myForm" value="" selected>Seleziona</option>
  <option id="sexuomo" name="radios" value="Male" form="myForm">Uomo</option>
  <option id="sexdonna" name="radios" value="Female" form="myForm">Donna</option>
</select>


<button onclick="validateForm()">Submit</button>
<form name="myForm" id="myForm" onsubmit="return validateForm()" method="post">
</form>

发布者:admin,转转请注明出处:http://www.yc00.com/questions/1745323027a4622528.html

相关推荐

发表回复

评论列表(0条)

  • 暂无评论

联系我们

400-800-8888

在线咨询: QQ交谈

邮件:admin@example.com

工作时间:周一至周五,9:30-18:30,节假日休息

关注微信