如何根据另一个值在 object 中获取值

Question

I could use some help cycling through an object and getting the difference in price between two products. For example, what is the difference in price between the big hammer and the small hammer?

Here's what I have so far

var myarray = [{product: "big hammer", price: 32},{product: "small hammer", price: 22},{product: "wrench", price: 15},{product: "saw", price: 55}];

getPriceDifference(myarray[0].product);


function getPriceDifference(currentProduct){

   if(currentProduct === "Big Hammer"){

     //do something...this is where I am stuck

   }



}

Thanks in advance.

Answer 1

There are multiple ways of iterating over arrays

myarray.map(item => {

})

myarray.foreach(item => {

})

Or if you change the structure of your data to the following, you do not have to iterate.

var products = {
  "big hammer": { price: 32 },
  "small hammer": { price: 22 },
  "wrench": { price: 15 },
  "saw": { price: 55 },
};

function getPriceDifference(product_1, product_2) {
  return Math.abs(products[product_1].price - products[product_2].price);
}

var difference = getPriceDifference("big hammer", "small hammer");
console.log(difference);

Answer 2

This works:

 var myarray = [{product: "big hammer", price: 32},{product: "small hammer", price: 22},{product: "wrench", price: 15},{product: "saw", price: 55}]; function getPriceDifference(first, second){ for(var i = 0; i < myarray.length; i++){ if(myarray[i]['product'] == first) price_first = myarray[i]['price']; if(myarray[i]['product'] == second) price_second = myarray[i]['price']; } return Math.abs(price_first - price_second); } console.log(getPriceDifference('small hammer', 'big hammer'));