javascript-打印表单值到console.log给出未定义的错误

Question

I was trying to print form values on submit to console.log to test. But getting a undefined message. Can't figure out where I am going wrong exactly. I have gone through various answers on StackOverflow but still no luck. Here is the code -

HTML

<form class="form-inline">
  <label class="required">* required </label>
  <div class="form-group">
    <input type="text" class="form-control inputArea" id="fullname" placeholder="Full Name *">
  </div>
  <div class="form-group">
    <input type="email" class="form-control inputArea" id="email" placeholder="Email *">
  </div>
  <div class="form-group">
    <input type="tel" class="form-control inputArea" id="phn" placeholder="Phone Number *">
  </div>
  <button type="submit" class="btn btn-default submit">Submit</button>
</form>

JavaScript

<script>
    var formInput = document.querySelectorAll('#fullname, #email, #phn');

    document.querySelector('form.form-inline').addEventListener('submit', function (e) {
        e.preventDefault();
        console.log(formInput.value);
    });
</script>

Answer 1

You are getting undefined because forminput is not a single object it has multiple objects which doesn't have property value .

You can get value by index like below

console.log(formInput[0].value);

Answer 2

You are querying the form before the values are inputted. The first line of your script should be inside the event listener:

<script>
    document.querySelector('form.form-inline').addEventListener('submit', function (e) {
        e.preventDefault();
        var formInput = document.querySelectorAll('#fullname, #email, #phn');
        console.log(formInput.value);
    });
</script>

The values are being query-ed on page-load. You need to wait until the user submits before you check the values.

Answer 3

You can try this. Hope it helps!

  function myFunction(){ var a = document.getElementById("fullname").value; var b = document.getElementById("email").value; var c = document.getElementById("phn").value; console.log(a); console.log(b); console.log(c); return false; } 

 <form class="form-inline" onsubmit = " return myFunction()"> <label class="required">* required </label> <div class="form-group"> <input type="text" class="form-control inputArea" id="fullname" placeholder="Full Name *"> </div> <div class="form-group"> <input type="email" class="form-control inputArea" id="email" placeholder="Email *"> </div> <div class="form-group"> <input type="tel" class="form-control inputArea" id="phn" placeholder="Phone Number *"> </div> <button type="submit" class="btn btn-default submit">Submit</button> </form>