How to combine array from an array with similar id?-CodePudding

Suppose I have a array like this.

const info = [
    {
        productId: "1",
        name: "This is product name 1",
        sellerId: "12",
        price: 30,
    },
    {
        productId: "2",
        name: "This is product name 2",
        sellerId: "12",
        price: 50
    },
    {
        productId: "3",
        name: "This is product name 3",
        sellerId: "13",
        price: 50
    }
]

**This is dynamic array. Array value can be changed.

Now I have to combine this array or filter this array. I have not any idea about how can I write function. But my result will be like this-

const result = [
    {
        sellerId: "12",
        productIds: [ //Combine products by similar sellerId
            {
                name: "This is product name 1",
                productId: "1"
            },
            {
                name: "This is product name 2",
                productId: "2"
            }
        ],
        total: 80 //Total price of this two product
    },
    {
        sellerId: "13",
        productIds: [
            {
                name: "This is product name 3",
                productId: "3"
            }
        ],
        total: 50
    }
]

Please do not close my question. I almost check all similar questions. But I have a different issue here. Just please help me.

CodePudding user response：

You could use .reduce and check if you already have that sellerId, if so, push the item and update total, else create the item:

const info = [
    {
        productId: "1",
        name: "This is product name 1",
        sellerId: "12",
        price: 30,
    },
    {
        productId: "2",
        name: "This is product name 2",
        sellerId: "12",
        price: 50
    },
    {
        productId: "3",
        name: "This is product name 3",
        sellerId: "13",
        price: 50
    }
]

const result = info.reduce((carry, el) => {
    const { sellerId, price, ...rest } = el;
    const i = carry.find((c) => c.sellerId === sellerId);

    if (!i) {
         carry.push({ sellerId, productIds: [rest], total: price })
    } else {
        i.productIds.push(rest);
        i.total  = price;
    }
    return carry;
}, []);

console.log(result);

CodePudding user response：

You can use Object.values() and Array#reduce() methods as follows:

const 
    input = [ { productId: "1", name: "This is product name 1", sellerId: "12", price: 30, }, { productId: "2", name: "This is product name 2", sellerId: "12", price: 50 }, { productId: "3", name: "This is product name 3", sellerId: "13", price: 50 } ],
    
    output = Object.values(
      input.reduce(
        (acc,{productId,name,sellerId,price}) =>
        ({
            ...acc,
            [sellerId]:{...(acc[sellerId] || {}), 
                sellerId, 
                productIds: [...(acc[sellerId] && acc[sellerId]['productIds'] || []), 
                {name,productId}]
            }
        }),
      {})
    );
    
    console.log( output );