Why is my JavaScript input value always empty, even though I'm typing in the field?

Caught in a Value Trap: Resolving Empty Input Values in JavaScript

When attempting to retrieve the value property from an input field for data retrieval, you may encounter an unexpected error: an empty input value regardless of what you type. The mystery may seem perplexing if you have successfully targeted the correct input field and button.

Let's delve into the root cause of this issue. JavaScript variables, like inputValue in your code, hold a snapshot of the value at the time they are created. So, when you execute the script initially, the inputValue variable is assigned the empty string at page load.

Unfortunately, this variable remains unchanged despite subsequent modifications to the input field's value. This is because JavaScript strings are immutable and cannot be altered once assigned. Therefore, any keystrokes you make in the input field are not reflected in the inputValue variable.

Resolving the Problem

To overcome this challenge, you have two options:

1. Query the Element Every Time:

Instead of assigning the value to a variable during page load, query the element every time the button is clicked:

const testing = () => {
  const inputValue = document.getElementById("inputField").value;

  alert(inputValue);
};

This approach ensures that the inputValue variable always contains the latest value entered into the input field.

2. Use a Reference to the Element:

Alternatively, you can keep a reference to the element and query the value property dynamically:

const inputElement = document.getElementById("inputField");
const testing = () => alert(inputElement.value);

By dynamically querying the value property, you avoid the potential pitfalls of using a static variable and guarantee that you work with the current input value.

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