无法将文本框的值分配给变量

Question

I'm trying to read the value from a textbox and it returns nothing.

Within the console, it simply shows a white line, with the line number of the console.log statement.

 var amount = document.getElementById("billAmt").value; document.getElementById('calculate').addEventListener('click', function() { console.log(amount); });

 <input id="billamt" type="text" placeholder="Bill Amount"> <button type="button" id="calculate">Calculate!</button>

Answer 1

There are couple of issues in your code:

1. Typo in billamt . It should be billAmt in HTML or change either of them to make same
2. You need to get the value inside the click function.

 document.getElementById('calculate').addEventListener('click', function() { var amount = document.getElementById("billAmt").value; console.log(amount); });

 <input id="billAmt" type="text" placeholder="Bill Amount"> <button type="button" id="calculate">Calculate!</button>