How to Retrieve Raw Input from an HTML5 Number Input Field, Even if It's Invalid?

Retrieving Raw Input from HTML5 Number Input

In HTML5, the element allows the user to input numerical values. However, if the input is invalid (e.g., contains non-numerical characters), its value property returns an empty string.

The Problem:

How can we retrieve the raw input from a field, including invalid text?

The Solution:

While the specifications prevent retrieval of invalid values, there is no way to determine whether the input is empty or contains invalid text. Therefore, a different approach is required.

Alternative Approach:

Instead of relying on the value property, we can use an event listener on the input element to capture the user's input in real-time.

Code Example:

const numberInput = document.getElementById('edQuantity');

numberInput.addEventListener('input', (event) => {
  const rawValue = event.target.value;

  if (isNaN(rawValue)) {
    // Input is invalid text; color it red
    numberInput.classList.add('error');
  } else {
    // Input is a valid number; color it green
    numberInput.classList.remove('error');
  }
});

This script attaches an event listener to the element that captures the input value whenever it changes. It then checks whether the value is a valid number; if it's not, it colors the input red; otherwise, it colors it green.

Note:

This approach allows you to get the raw input, including invalid text, but the validation and handling of invalid input are up to you.

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