Spreadsheet formula and result in single text input-CodePudding

I have been searching for a way to type a formula into a single text input and when I hit the Enter key, the formula executes and the result replaces the formula in the same input box.

Really I want it to function exactly like an Excel cell. https://formulajs.info/functions/ does what I want, except there is a button to click and the result comes back in a separate input box.

I'm learning to write code, so I don't have the skills to reverse-engineer that plugin, and that was the only thing I could find online that was even close. Most of my searches just keep turning up grid spreadsheets with formulas and it is important for me to keep it to a single input.

Does anyone have any ideas of where I might find something already made or how I could make something like that for myself? I don't need all the fancy engineering, financial, etc types. I just want simple math with an option for parentheses to nest formulas, ie 2*6 (8/4) gives a result of 14.

CodePudding user response：

You can try this for simple JavaScript

const input = document.getElementById('formulaInput');

input.addEventListener('keydown', (event) => {
  if (event.keyCode === 13) {  // Enter key Code
    const formula = input.value;
    const result = eval(formula);
    input.value = result;
  }
});