将 for 循环的结果压入数组

Question

I have an existing array:

array = [
  { type: 'animal', color: 'green' },
  { type: 'plant', color: 'red' }]

I am making a for loop based on this array.

for(let i=0; i<array.length; i++){
    //make get request from database
    //first query result
    newObject = {type: 'plant', size: 'small'}

    //second query result
    newObject = {type: 'animal', size: 'large' }
}

If the type of newObject matches that of the array, then, push or append that to array. This is my desired result:

array = [
  { type: 'animal', color: 'green', size: 'large' },
  { type: 'plant', color: 'red', size: 'small' }]

Answer 1

Try this.

 for(let i=0; i<array.length; i++){
        if(array[i].type == 'plant'){
           array[i].size = 'small';
         }
        if(array[i].type == 'animal'){
           array[i].size = 'large';
         }
    }

To check console.log(array);

Hope useful.

Answer 2

Maybe the best way is doing this:

const idx = array.findIndex(x => x.type === newObject.type );
array[idx] = {...array[idx], ...newObject};

Answer 3

I'd recommend using a data structure that works better for you than an Array . A Map or an object lets you index data by a key so you don't have to scan through an Array to find something multiple times:

const thingsByType = new Map([
  ['animal', { color: 'green' }],
  ['plant', { color: 'red' }]
]);

thingsByType.get('animal').size = 'small';

// or

const thingsByType = {
  animal: { color: 'green' },
  plant: { color: 'red' }
};

thingsByType.animal.size = 'small';

You can create a Map or Object from an Array if you cannot help starting from that structure:

const thingsByType = new Map(things.map(thing => [thing.type, thing])); 

// or

const thingsByType = things.reduce(
  (result, thing) => Object.assign(result, { [thing.type]: thing }), 
  {});

Answer 4

Just forked from @A.khalifa above. This is also another workaround if you don't know exactly what is being fetched from the database.

for(let i=0; i<array.length; i++){
    // make get request from database
    // first query result
    // newObject = {type: 'plant', size: 'small'}
    // -- This is based on the newObject being fetched above
    if(array[i].type == newObject.type){
       array[i].size = newObject.size;
     }
}

Answer 5

Hope this result will be useful. But one way or another you have to run the loop for each newObject. Here also 'type' consider as the key as you have to consider fixed one key property.

array = [
  { type: 'animal', color: 'green' },
  { type: 'plant', color: 'red' }];

let newObject = {type: 'animal', size: 'large' }

for(let i=0; i<array.length; i++){

    if(array[i].type == newObject.type){
      for (let key of Object.keys(newObject)) {
          array[i][key] = newObject[key]

      }
    }

}

console.log(array);

//    array[
//       {type: "animal", color: "green", size: "large"},
//       {type: "plant", color: "red"}
//    ]