I have an array of objects, objects that contain an order: number; property.

I want for each object in that array that has the order property higher than a specific value to have it decreased it by one.

Any simple way to achieve this?

myArray.forEach(x => x.order >= someValue)...

CodePudding user response：

You can map the result, updating the value when >= someValue

const someValue = 3;

const result = [
  { order: 1 }, 
  { order: 2 }, 
  { order: 3 }, 
  { order: 4 }
].map(x => x.order >= someValue ? { ...x, order: x.order - 1 } : x);

console.log(result);

CodePudding user response：

With array.reduce

const value = 2;
const testArray = [{ order: 1 }, { order: 1 }, { order: 3 }];

const result = testArray.reduce((acc, curr) => {
  if (curr.order > value) {
    return [...acc, { ...curr, order: curr.order - 1 }];
  }
  return [...acc, curr];
}, []);
console.log(result);

CodePudding user response：

Several options to reach this:

1. Adding functionality to Array.prototype.

   if(!Array.prototype.decreaseOrderIfBiggerThan) {
     Array.prototype.decreaseOrderIfBiggerThan = function(value) {
       if(!value || typeof value != 'number') return this;
       return this.map((el) => ({ 
         ...el, 
         order: el?.order > value ? --el.order : el.order 
       }))
     }
   }
   

2. Simply mapping:

   myArray = myArray.map((el) => ({ 
     ...el, 
     order: el?.order > value ? --el.order : el.order 
   }))
   

3. Mutating original array: it's basically #2 method but without assigning new array to original one and with forEach.

Hopes this is what you needed.