类别相同时如何加数字？

Question

到目前为止我正在尝试的代码

let data = [
{size: 1180160, category: "Keswick", index: 1},
{size: 1059328, category: "HCOPA", index: 2},
{size: 30720, category: "HCOPA", index: 3},
{size: 493056, category: "Darhan Saluja", index: 4},
{size: 267776, category: "CRSA", index: 5},:
{size: 328704, category: "Arundel", index: 6}
{size: 73216, category: "Arundel", index: 7}

data.forEach((product, index) => {

           let size = 0;
           if (product.category !== lastCategory) {
             size = product.size + size;
             rows.push(
                <ProductCategoryRow size={size}
                                    category={product.category}
                                    key={product.category}/>
            );
        }
        rows.push(
            <ProductRow
                product={product}
                key={product.name} index={index}/>
        );
        lastCategory = product.category;

    });

我要计算具有相同类别的尺寸。 这样就可以作为道具的传递对象

Answer 1

我建议您首先创建一个新对象，其中包含所需的所有数据以及所需的属性的总和，然后使用该对象执行所需的逻辑。

请查看下面的代码段，并根据需要进行调整。

 let data = [ {size: 1180160, category: "Keswick", index: 1}, {size: 1059328, category: "HCOPA", index: 2}, {size: 30720, category: "HCOPA", index: 3}, {size: 493056, category: "Darhan Saluja", index: 4}, {size: 267776, category: "CRSA", index: 5}, {size: 328704, category: "Arundel", index: 6}, {size: 73216, category: "Arundel", index: 7}] const dataWithSum = data.reduce((acc, current) => { acc[current.category] = acc[current.category] ? acc[current.category] + current.size : current.size; return acc }, {}) console.log(dataWithSum) 

Answer 2

您可以创建数据块，然后将其呈现为

let data = [
{size: 1180160, category: "Keswick", index: 1},
{size: 1059328, category: "HCOPA", index: 2},
{size: 30720, category: "HCOPA", index: 3},
{size: 493056, category: "Darhan Saluja", index: 4},
{size: 267776, category: "CRSA", index: 5},
{size: 328704, category: "Arundel", index: 6},
{size: 73216, category: "Arundel", index: 7}]

const chunk = data.reduce((acc, item) => {
    if(acc[item.category]) {
      acc[item.category] = acc[item.category].concat(item)
    } else {
      acc[item.category] = [item];
   }
   return acc
}, {})

Object.keys(chunk).forEach((category, index) => {
   rows.push(
      <ProductCategoryRow 
          size={size}
          category={category}
          key={category}/>
  );
  chunk[category].forEach((product, index)) => {
     rows.push(
        <ProductRow
            product={product}
            key={product.name}/>
     );
  }
});

Answer 3

使用reduce和findIndex 。 findIndex将用于查找新数组是否具有与类别匹配的任何对象，如果匹配则更新大小，否则添加类别名称及其大小

 let data = [{ size: 1180160, category: "Keswick", index: 1 }, { size: 1059328, category: "HCOPA", index: 2 }, { size: 30720, category: "HCOPA", index: 3 }, { size: 493056, category: "Darhan Saluja", index: 4 }, { size: 267776, category: "CRSA", index: 5 }, { size: 328704, category: "Arundel", index: 6 }, { size: 73216, category: "Arundel", index: 7 } ] var reduceCat = data.reduce(function(acc, curr) { // find the index of the category // return -1 if the category is not present var ifCatAvailable = acc.findIndex(function(item) { return curr.category === item.category; }) // if category is not present then // add the category and it's size if (ifCatAvailable === -1) { let locObj = { category: curr.category, size: curr.size } acc.push(locObj) // if catgory is present then update it's size } else { acc[ifCatAvailable].size += curr.size } return acc; }, []); console.log(reduceCat) 

Answer 4

您还可以创建类别数组并将结果放入数组结果= [类别，大小]

let data = [
{size: 1180160, category: "Keswick", index: 1},
{size: 1059328, category: "HCOPA", index: 2},
{size: 30720, category: "HCOPA", index: 3},
{size: 493056, category: "Darhan Saluja", index: 4},
{size: 267776, category: "CRSA", index: 5},
{size: 328704, category: "Arundel", index: 6},
{size: 73216, category: "Arundel", index: 7}];

let categories = [];
let result = [];

data.forEach((product, index) => {
            if( !categories.includes(product.category) ) {
              categories.push(product.category);
              result.push({
                category : product.category,
                size: product.size
                });
            }
            else{
              result.find(x => x.category === product.category).size += product.size;
            }    
    });
console.log(data, categories, result);