如何做一个简单的计算器

Question

The task is to implement a function , a simple addition and subtraction calculator that:

• Takes three arguments, two integers, firstArg, SecondArg and a string operation that is either "+" or "-"
• Returns a value depending on operation: If operation is + then it returns the sum of the firstArg with the secondArg. If operation is - then ir returns the subtraction of the firstArg with the secondArg. If operation isn't none then it returns "invalid operation"

Can someone help?

Answer 1

function name(a0, a1, a2) {
  return a2 === "+"? a0 + a1: a0 - a1;
}

Answer 2

Here is the function, as you asked:

const calculator = function(firstArg, secondArg, operationType) {
    if (operationType === '+') {
        return firstArg + secondArg;
    } else if (operationType === '-') {
        return firstArg - secondArg;
    }
}

Answer 3

Below is the function as you asked. The switch statement in JavaScript can be learnt about here . If you wanted to use something maybe slightly simpler have a look at the other answers.

function simpleAdditionAndSubtractionCalculator(num1, num2, operatorType) {
    switch(operatorType) {
        case "-":
            return num1 - num2;
            break;
        case "+":
            return num1 + num2;
            break;
        default:
            return "Invalid operation!";
            break;
    }
}

Answer 4

 function process (operation, a, b) { if(operation === '+'){ return a + b; }else if(operation === '-'){ return a - b; }else{ return "invalid operation"; } } console.log( process('+',3,5) );

Answer 5

You need to use js eval function

function simpleAdditionAndSubtractionCalculator(num1, num2, operatorType) {
    return eval(num1 + operatorType + num2)
}