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lromeraj
Asked: 2020-12-04 05:28:44 +0800 CST 2020-12-04 05:28:44 +0800 CST

How can I operate the numbers entered in an <input> directly in Javascript? [duplicate]

  • 772

What I intend is to take the numbers of a <input>and then operate them directly from JavaScript:

If, for example, <input>it is entered ((2+2)/4)*3, the answer is:3

Solution Based on the answers received, I concluded the following solution to the question:

JavaScript:

function calc() {

    //Coger el valor del input
    var value = document.getElementById("value").value;

    //Operar los datos recogidos
    var operation = eval(value); 

        //Mostrar el resultado
        alert(operation); 
}

HTML:

<body>
    <input id="value" type="number">
    <button id="calculate" onclick="calc()">Calculate</button>
</body>
javascript

2 Answers

  1. Best Answer

    You could collect the value directly from the input and use the eval.

    var tuInput = document.getElementById("tuInput");
var operacion = tuInput.value;
var suma = eval(operacion);
    • 5

  2. You can use the Function constructor :

    var sumar = document.getElementById("sumar").value;
console.log(new Function('return ' + sumar)());
    <input type="text" id="sumar" value="(2+2)/2">

    • 0