How to partition input field to appear as separate input fields on screen?

Question

Look at the image:

I want design something like in the image, where a 4 digit one time password (OTP) is to be entered by user. Right now I have achieved this by 4 separate inputs and then combining values in javascript:

<input type="text" class="form-control" placeholder="0" maxlength="1"  />
<input type="text" class="form-control" placeholder="0" maxlength="1" />
<input type="text" class="form-control" placeholder="0" maxlength="1" />
<input type="text" class="form-control" placeholder="0" maxlength="1" />

I am not sure if this is correct approach. I think there must be some styling options by which one input textbox would appear as partitioned one like in the image. Is it possible using bootstrap? How to style one input control to be appeared as partitioned field of inputs?

Answer 1

You don't have to keep four separate fields.

First, you should adjust the character spacing, and then adjust the border style of bottom.

#partitioned {
  padding-left: 15px;
  letter-spacing: 42px;
  border: 0;
  background-image: linear-gradient(to left, black 70%, rgba(255, 255, 255, 0) 0%);
  background-position: bottom;
  background-size: 50px 1px;
  background-repeat: repeat-x;
  background-position-x: 35px;
  width: 220px;
  outline : none;
}

<input id="partitioned" type="text" maxlength="4" />

--EDIT to fix 5 underlines for 4 character ugliness--

var obj = document.getElementById('partitioned');
obj.addEventListener('keydown', stopCarret); 
obj.addEventListener('keyup', stopCarret); 

function stopCarret() {
    if (obj.value.length > 3){
        setCaretPosition(obj, 3);
    }
}

function setCaretPosition(elem, caretPos) {
    if(elem != null) {
        if(elem.createTextRange) {
            var range = elem.createTextRange();
            range.move('character', caretPos);
            range.select();
        }
        else {
            if(elem.selectionStart) {
                elem.focus();
                elem.setSelectionRange(caretPos, caretPos);
            }
            else
                elem.focus();
        }
    }
}

#partitioned {
  padding-left: 15px;
  letter-spacing: 42px;
  border: 0;
  background-image: linear-gradient(to left, black 70%, rgba(255, 255, 255, 0) 0%);
  background-position: bottom;
  background-size: 50px 1px;
  background-repeat: repeat-x;
  background-position-x: 35px;
  width: 220px;
  min-width: 220px;
  outline:none;
}

#divInner{
  left: 0;
  position: sticky;
}

#divOuter{
  width: 190px; 
  overflow: hidden;
}

<div id="divOuter">
    <div id="divInner">
        <input id="partitioned" type="text" maxlength="4" autocomplete="off" />
    </div>
</div>

I think this can be a starting point.

Hope this will help...