how to exlude empty spaces from "if-else" statments - JS

I searched for how to exclude empty spaces like " " or " " or " " from an if statments but i didnt find any relevant topic

i have an html page which add a value to an array everytime the user types in a value inside the input field
but i want to exclude the spaces, for example if the user enter only empty spaces, i dont want them to be pushed inside the values[] array

this is my jscode :

const values = []
const inputEL = document.getElementById("field-input")
  if (inputEL.value){
    values.push(inputEL.value)
    inputEL.value = ""
  }

I tried this but it didn't work as expected, user still can enter empty spaces and they are pushed inside the array:

if (!inputEL.value || inputEL.value === " "){
    console.log("field input is  empty / user enter empty spaces")
else{
    values.push(inputEL.value)
    inputEL.value = ""
}

You could use trim() to remove whitespaces from the beginnen and end of the string.

So if the input is " ", you well trim() it down to "" which is a falsy value in your if:

const values = []
const inputEL = document.getElementById("field-input");
const trimmed = inputEl.value.trim();
if (trimmed){
    values.push(trimmed)
    inputEL.value = ""
}

You could also use a pattern and a required attribute to combine the requirement

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-html -->

<form>
  <input name="name" required pattern=".*\S+.*" title="can't include only whitespace">
  <input type="submit">
</form>

<!-- end snippet -->

then you can also use input.validity.valid to check if it's valid or not

You can use string.trim() method, it return a new array with whitespaces removed from both ends, (start and end) without modifying the original one