Home > Back-end >  Looping over an object to change values inside
Looping over an object to change values inside

Time:07-07

I am trying to send an object to an api and my object contains arrays that I want to turn into strings. However I am having trouble returning the new object with the arrays turned to strings. My goal is to have a copy of the original object with all the arrays turned into strings.

const object1 = {
  a: ["TX", "CA", "LA"],
  b: 42,
  c: false
  d: []
};

for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(object1[key]) && object1[key].length > 0){
   object1[key].toString()
  }
}
console.log(object1)
//returns the original object without `a` as string

CodePudding user response:

You are not assigning the new value to anything, so it is being lost with each loop. Try:

object1[key] = object1[key].toString()

const object1 = {
  a: ["TX", "CA", "LA"],
  b: 42,
  c: false,
  d: []
};

for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(object1[key]) && object1[key].length > 0){
   object1[key] = object1[key].toString()
  }
}
console.log(object1)
//returns the original object without `a` as string

This way with every for loop, you reassign object1[key] to object1[key].toString()

CodePudding user response:

Use join on the arrays to form strings.

const object1 = {
  a: ["TX", "CA", "LA"],
  b: 42,
  c: false,
  d: []
};

for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(value)) {
    object1[key] = value.join(',');
  }
}
console.log(object1)

If you need to get arrays back later, use split.

CodePudding user response:

You should use join(",")

const object1 = {
 a: ["TX", "CA", "LA"],
 b: 42,
 c: false,
 d: []
};

 for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(object1[key]) && object1[key].length > 0){
   object1[key] = object1[key].join(",")
 }
}
console.log(object1)

CodePudding user response:

First, add a , after false. Then in the if statement change:

object1[key].toString();

To:

object1[key] = value.toString();

DEMO

const object1 = {
  a: ["TX", "CA", "LA"],
  b: 42,
  c: false,
  d: []
};

for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(value) && value.length > 0) {
     object1[key] = value.toString();
  }
}
console.log(object1)

NOTE

Pursuant to My goal is to have a copy of the original object with all the arrays turned into strings, if you'd like to convert [] to "", then remove && object1[key].length > 0 from the if condition.

const object1 = {
  a: ["TX", "CA", "LA"],
  b: 42,
  c: false,
  d: []
};

for (const [key, value] of Object.entries(object1)){
  if(Array.isArray(value)) {
     object1[key] = value.toString();
  }
}
console.log(object1)

  • Related