Is there an easier way to combine several if statements using an array in javascript-CodePudding

I have a form where a user enters their address. This then checks their address against several destinations in the UK to see which city is their nearest.

I want each destination to have different prices, for example London, UK = 50, Birmingham, UK = 200 etc.

I have written a pretty rudimentary if statement which checks the city that is returned and calculates the price. However, I'm wondering if there is a neater solution to this as it feels a bit obtuse:

if(closestCities[0].cityName == "Coventry, UK") {
  travelExpenses = 10;
} else if (closestCities[0].cityName == "London, UK"){
  travelExpenses = 50;
} else if (closestCities[0].cityName == "Margate, UK"){
  travelExpenses = 100;
} else if (closestCities[0].cityName == "Bristol, UK"){
  travelExpenses = 20;
} else if (closestCities[0].cityName == "Tamworth, UK"){
  travelExpenses = 15;
} else if (closestCities[0].cityName == "Birmingham, UK"){
  travelExpenses = 200;
} else {
  travelExpenses = 30;
}

CodePudding user response：

Why don't you create an object:

let map = {
 "Margate, UK": 100,
 "Bristol, UK": 20 // etc.
}

It seems you also want a default value. I think in your case you could utilize the nullish coalescing operator:

The nullish coalescing operator (??) is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand

travelExpenses = map[closestCities[0].cityName] ?? 30;

CodePudding user response：

You could also define a dictionary for your expenses

let expenses = {
  "Coventry, UK": 10, 
  "London, UK": 20,
  ...

}

let travelExpenses = expenses[closestCities[0].cityName] || 30;

If you have any city, with expenses 0, you have to do it as follows

let travelExpenses = expenses[closestCities[0].cityName];
if (travelExpenses === undefined) travelExpenses = 30;

CodePudding user response：

You can try destructuring object along with switch statement to make it highly readable.

const { cityName } = closestCities[0]
switch (cityName) {
    case "Coventry, UK":   travelExpenses = 10;
                            break;
    case "London, UK": travelExpenses = 20
                        break;
    ...
}