Prompt to enter name into input

Question

I'm planning to create a JavaScript prompt where you can enter your name and it will go to the 's value. How can I make the code work? I tried the below code but it seems it needed a jQuery 1.7.1

function getName() {
    do {
        var name=prompt("Please enter your CLAM username");
    }
    while(name.length < 4);
    $('#myinput').val(name);
}

getName();

HTML

<input id="myinput"/>

I expect the output to be <input id="myinput" value"name from prompt">

Answer 1

You don't actually need jQuery for this:

function getName() {
  do {
    var name = prompt("Please enter your CLAM username");
  }
  while (name.length < 4);
  document.getElementById("myinput").value = name;
}

getName();

<input id="myinput" />

If you really want to use jQuery, then import a newer version:

function getName() {
  do {
    var name = prompt("Please enter your CLAM username");
  }
  while (name.length < 4);
  $("#myinput").val(name);
}

getName();

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>
<input id="myinput" />

Answer 2

Because the line of code $('#myinput').val(name) is jquery syntax.

You can change it to javascript by

document.getElementById('myinput').value = name;

it is equal with $('#myinput').val(name);

function getName() {
    do {
        var name=prompt("Please enter your CLAM username");
    }
    while(name.length < 4);
    document.getElementById('myinput').value = name;
}

getName();

  

<input id="myinput"/>

Answer 3

$('myinput').val(name);

is for jquery only. if you don't want to use jquery then use this

document.getElementById('myinput').value = name;

for a pure javascript..

Here is my answer for this.

<input id="myinput"/>

<script type="text/javascript">
    function getName() {
    do {
        var name=prompt("Please enter your CLAM username");
    }
    while(name.length < 4);
    document.getElementById('myinput').value = name;
}
getName();
    </script>

note: don't put your <input id="myinput"/> at the bottom or else you will get null. put it above the script.