let data1 = [{project_code: "110",project_text: "SampleProject1",location: "Seattle",startingCost: 0,actualCost: 399.99},{project: "110",project_text: "SampleProject1",location: "Bellevue",startingCost: 0,actualCost: 599.99}]; let data2 = [{project: "110",project_text: "SampleProject1",location: "Seattle",startingCost: 249.99,actualCost: ""},{project: "110",project_text: "SampleProject1",location: "Bellevue",startingCost: 699.99,actualCost: ""},{project: "110",project_text: "SampleProject1",location: "North Gate",startingCost: 899.99,actualCost: 1199.99}] data2.forEach((obj) => { let ob = data1.find((e) => e.location == obj.location); // YOU CAN ADD OTHER CONDTIONS HERE WITH && OPERATOR if (ob !== undefined) { obj.actualCost = ob.actualCost; } }); console.log(data2);

El código anterior anulará data2.

 let data1 = [{project_code: "110",project_text: "SampleProject1",location: "Seattle",startingCost: 0,actualCost: 399.99},{project: "110",project_text: "SampleProject1",location: "Bellevue",startingCost: 0,actualCost: 599.99}]; let data2 = [{project: "110",project_text: "SampleProject1",location: "Seattle",startingCost: 249.99,actualCost: ""},{project: "110",project_text: "SampleProject1",location: "Bellevue",startingCost: 699.99,actualCost: ""},{project: "110",project_text: "SampleProject1",location: "North Gate",startingCost: 899.99,actualCost: 1199.99}] var final_result = []; data2.forEach(({...obj}) => { let ob = {...data1.find((e) => e.location == obj.location)}; //{...data}; used to Clone Object without reference to do not override data1 if (Object.keys(ob).length !== 0) { ob.startingCost = obj.startingCost; final_result.push(ob); } else { final_result.push(obj); } }); console.log(final_result);

1. {...obj} en forleach ( forEach(({...obj}) ) utilizado para restringir la modificación del objeto data2 al modificar final_result

Así es como lo haría. Como sugirieron los comentarios, ¿qué propiedad se supone que es única? Sería el criterio que usaría para encontrar los datos en la otra matriz, usé la ubicación porque eso es lo único que parecía ser diferente. Por supuesto, puede usar más de una propiedad para encontrar una coincidencia como: item.project === obj.project && item.location === obj.location

 data2.forEach(obj=>{ let object1 = data1.find(item=>item.location === obj.location); if(object1){ object1.startingCost = object1.startingCost || obj.startingCost; object1.actualCost = object1.actualCost || obj.actualCost; } else{ data1.push(obj); }

})

Esto sería predeterminado para mantener los datos de la matriz data1 si ambas matrices tienen datos para un objeto. Así que cámbielo por las necesidades de su programa.

Intente usar Array.reduce .

Lógica

• data2 con Array.reduce .
• Verifique el nodo coincidente en data1 desde data2 .
• Si se encuentra un nodo coincidente, combine el costo startingCost y el actualCost .
• Aunque esto cubre el requisito, no se detenga aquí. Debe verificar que cada nodo en data1 ya se haya cubierto en el resultado. Si eso no está cubierto, empuje el nodo que falta para que resulte.

   const data1 = [{ project: "110", project_text: "SampleProject1", location: "Seattle", startingCost: 0, actualCost: 399.99 }, { project: "110", project_text: "SampleProject1", location: "Bellevue", startingCost: 0, actualCost: 599.99 }]; const data2 = [{ project: "110", project_text: "SampleProject1", location: "Seattle", startingCost: 249.99, actualCost: "" }, { project: "110", project_text: "SampleProject1", location: "Bellevue", startingCost: 699.99, actualCost: "" }, { project: "110", project_text: "SampleProject1", location: "North Gate", startingCost: 899.99, actualCost: 1199.99 }]; const result = data2.reduce((acc, curr) => { const matchingNode = data1.find((node) => node.project === curr.project && node.project_text === curr.project_text && node.location === curr.location); if(matchingNode) { const updatedNode = { ...matchingNode }; // Take a copy of matching node updatedNode.startingCost = matchingNode.startingCost || curr.startingCost; updatedNode.actualCost = matchingNode.actualCost || curr.actualCost; acc.push(updatedNode); } else { acc.push(curr); } return acc; }, []); // Since we have looped through data2 to generate the array, // we have to ensure that we have not missed any node from data1 aswell data1.forEach((node) => { const matchingNode = result.find((resultNode) => node.project === resultNode.project && node.project_text === resultNode.project_text && node.location === resultNode.location); if (!matchingNode) { result.push(node); } }) console.log(result);