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JS Bits Bill
JS Bits Bill

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HTMLInputElement.valueAsNumber

By default, <input> value's are a string type:

<input type="number" id="my-num">
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const inputEl = document.querySelector('#my-num');

inputEl.addEventListener('blur', e => {
  const val = e.target.value;
  console.log(typeof val); // "string"
});
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But if the expected input is a number or date that we'll later have to do math with, we can easily capture the value as a number type with valueAsNumber:

const inputEl = document.querySelector('#my-num');

inputEl.addEventListener('blur', e => {
  const val = e.target.valueAsNumber;
  console.log(typeof val); // "number"
});
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Note that this only works with <input type="number"> and not type="text". No conversion necessary!⚡


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Top comments (1)

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Felquis Gimenes

Thank you for sharing, It is missing link to the oficial documentation.