javascript - JS 事件问题 - 存储提示值并稍后调用它们

Question

试图为自己构建一个计算器，它需要两个提示数字，然后有一组单独的按钮来评估它们

我遇到的问题如下，我将提示的 number1 和 number2 保存为变量，但是当我尝试在外部函数中调用变量时，它告诉我变量（number1 和 number2）没有定义

有什么帮助吗？

ps：我已经开始做添加按钮了，然后会添加sub/mult/div，只需要让第一个去

// the user is required to choose two sets of numbers that are then stored as variables
function numRequest() {
  var number1 = prompt('choose the first number to evaluate:');
  var number2 = prompt('choose the second number to evaluate:');
  // just an external checker to see if the prompt is being saved 
  console.log('first choice --> ' + number1);
  console.log('second choice --> ' + number2);
  // the numbers, stored as variables, are displayed on the calculator window
  document.getElementById('resBanner').innerHTML = ('you chose ' + number1 + ' and ' + number2);
}

// this is where the problem arises
// when i press the button that summons the function addition(), the two numbers arent
// defined for some reason 
function addition() {
  var res = Number(number1) + Number(number2);
  document.getElementById('resBanner').innerHTML = res;
}

// function subtraction() {}

// function division() {}

// function multiplication() {}

标签： javascripthtmldom-eventscalculator

Answer 1

试试这个方法。

// the user is required to choose two sets of numbers that are then stored as variables
let number1;
let number2;

function numRequest() {
  number1 = prompt('choose the first number to evaluate:');
  number2 = prompt('choose the second number to evaluate:');
  // just an external checker to see if the prompt is being saved 
  console.log('first choice --> ' + number1);
  console.log('second choice --> ' + number2);
  // the numbers, stored as variables, are displayed on the calculator window
  document.getElementById('resBanner').innerHTML = ('you chose ' + number1 + ' and ' + number2);
}

// this is where the problem arises
// when i press the button that summons the function addition(), the two numbers arent
// defined for some reason 
function addition() {
  var res = Number(number1) + Number(number2);
  document.getElementById('resBanner').innerHTML = res;
}

// function subtraction() {}

// function division() {}

// function multiplication() {}