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Error when creating array of objects in a javascript loop

I have a problem creating an array of objects. the problem is that you should only create 2 objects but you end up creating 8 objects, because each value of a property is inserted into a new object. I have an array of objects called columns, which is dynamic since the values and properties are changing

enter image description here
what I need is to create objects depending on the value of the row property, for example an object that only contains the same value of the row.

 example: [   
    { string1: 'CONTRAPARTIDA',string2: 'NOMBRE',string3: null, number1: 'Orden', number2: 'VALOR ENV.' number3: null},      object with row value = 1   
    { string1: 'CONTRAPARTIDA',string2: 'NOMBRE',string3: null, number1: 'Orden', number2: 'VALOR ENV.' number3: null},      //object with row value = 2    

With this code I try to create my 2 objects, but unfortunately more objects are created than desired.

 for(let a in columnas){
 //I can't do this validation because as the column array is dynamic I don't know how many rows come in //the array.
     //if(columnas[a].fila ==1)  
    
         arrayFinal.push({
      
    // validations to match the campoDb with the new array property and insert the value
                         string1: (columnas[a].campoDb==='STRING1' ? columnas[a].nombre : null),
                         string2:(columnas[a].campoDb==='STRING2' ? columnas[a].nombre : null),
                         string3: null,
                         number1: (columnas[a].campoDb==='NUMBER1' ? columnas[a].nombre : null),
                         number2:(columnas[a].campoDb==='NUMBER2' ? columnas[a].nombre : null),
                         number3: null,
                         });

enter image description here
but as an attachment in the image 8 objects are created and only one property is filled and the correct thing would be this only 2 objects with these values.

 Example: [   
{ string1: 'CONTRAPARTIDA',string2: 'NOMBRE',string3: null, number1: 'Orden', number2: 'VALOR ENV.' number3: null},   
{ string1: 'CONTRAPARTIDA',string2: 'NOMBRE',string3: null, number1: 'Orden', number2: 'VALOR ENV.' number3: null},

const columnas = [
  { nombre: 'ORDEN', fila: 1, campoDb: 'NUMBER1' },
  { nombre: 'CONTRAPARTIDA', fila: 1, campoDb: 'STRING1' },
  { nombre: 'NOMBRE', fila: 1, campoDb: 'STRING2' },
  { nombre: 'VALOR ENV.', fila: 1, campoDb: 'NUMBER2' },
  { nombre: 'ORDEN', fila: 2, campoDb: 'NUMBER1' },
  { nombre: 'CONTRAPARTIDA', fila: 2, campoDb: 'STRING1' },
  { nombre: 'NOMBRE', fila: 2, campoDb: 'STRING2' },
  { nombre: 'VALOR ENV.', fila: 2, campoDb: 'NUMBER2' },
];  

let arrayFinal = [];
 for(let a in columnas){
  if(columnas[a].fila ==1) //no puedo hacer esta validacion xq como el arreglo columna es dinamico no se cuantas filas vengan en el areglo
    arrayFinal.push({
     string1: (columnas[a].campoDb==='STRING1' ? columnas[a].nombre : null),
     string2:(columnas[a].campoDb==='STRING2' ? columnas[a].nombre : null),
     string3: null,
     number1: (columnas[a].campoDb==='NUMBER1' ? columnas[a].nombre : null),
     number2:(columnas[a].campoDb==='NUMBER2' ? columnas[a].nombre : null),
     number3: null,
     });arrayFinal


 }
   console.log(arrayFinal);

I need some solution or recommendation on what I can do or what I can change from my code to make what I’m trying to do easier.

Answer

You have to filter columns based on criteria and reduce the result into an object.

const columnas = [
  { nombre: 'ORDEN', fila: 1, campoDb: 'NUMBER1' },
  { nombre: 'CONTRAPARTIDA', fila: 1, campoDb: 'STRING1' },
  { nombre: 'NOMBRE', fila: 1, campoDb: 'STRING2' },
  { nombre: 'VALOR ENV.', fila: 1, campoDb: 'NUMBER2' },
  { nombre: 'ORDEN', fila: 2, campoDb: 'NUMBER1' },
  { nombre: 'CONTRAPARTIDA', fila: 2, campoDb: 'STRING1' },
  { nombre: 'NOMBRE', fila: 2, campoDb: 'STRING2' },
  { nombre: 'VALOR ENV.', fila: 2, campoDb: 'NUMBER2' },
]; 

var result = [1, 2].map(i => columnas.filter(c => c.fila === i).reduce((acc, cur) => { acc[cur.campoDb] = cur.nombre; return acc }, {}));

console.log(result)