javascript - 循环数组并填充矩阵 - JS

Question

我想动态填充矩阵表。我有这部分 API 响应:

"Characteristics": [
            {
                "Description": "Benefits - Pay Related",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - Preapproved",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - Age/Service Weighted Plan",
                "Years": [
                    2018,
                    2017
                ]
            },
            {
                "Description": "Benefits - Profit Sharing",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - 404c",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - Participant Directed",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - 401(K)",
                "Years": [
                    2018,
                    2017
                ]
            },
            {
                "Description": "Benefits - 401(m) Arrangement",
                "Years": [
                    2018,
                    2017,
                    2016
                ]
            },
            {
                "Description": "Benefits - Auto Enrollment",
                "Years": [
                    2018,
                    2017
                ]
            }

如您所见，“描述”始终存在，但并非所有年份都存在。最后我想要呈现这样的东西:

提供的表格与数据无关 - 正如您在“福利 - 年龄/服务加权计划”中看到的那样，“年份”中没有 2016 年，所以我希望有“N”。我有功能从数据的其他部分检测独特的年份，其中包含提供任何信息的所有年份。这是 API 响应:

const uniqueYearsPension = data => {
  return data.map(element => {
    return element.Year;
  });
};

我尝试像这样填充表格:

<table className="table table-striped table-bordered table-sm table-hover">
                  <thead className="thead-dark">
                    <tr>
                      <th>Description</th>
                      {DataExtract.uniqueYearsPension(
                        props.types[2][index]
                      ).map((el, ind) => {
                        return <th key={ind}>{el}</th>;
                      })}
                    </tr>
                  </thead>
                  <tbody className="table-hover">
                    {element.Characteristics &&
                      element.Characteristics.map((e, i) => {
                        return (
                          <tr key={i}>
                            <td>{e.Description}</td>
                            {e.Years.reverse().map((year, yearID) => {
                              console.log(year);
                              return DataExtract.uniqueYearsPension(
                                props.types[2][index]
                              ).map((el, ind) => {
                                console.log(year);
                                if (year == el) {
                                  return <td key={yearID}>Y</td>;
                                }
                              });
                            })}
                          </tr>
                        );
                      })}
                  </tbody>
                </table>

但是它会按 1 填充第 1 行，如果缺少 2016 年，则会将 2017 年的结果放入此列中，因此 2018 年是空的而不是 2016 年 - 这绝对是正常的。如果我在这里添加 else 语句:

if (year == el) {
                                  return <td key={yearID}>Y</td>;
                                } else return <td key={yearID}>N</td>

它正在行上打印许多结果。有什么想法如何像矩阵一样填充我的表格吗？

Answer 1

首先尝试将uniqueYearsPension的结果保存到变量中以避免重新计算。 然后在渲染期间 tr 只需映射所有年份并检查 e.Years 是否包含该值。 代码如下所示:

const uniqueYears = DataExtract.uniqueYearsPension(props.types[2][index]);
...
...
<table className="table table-striped table-bordered table-sm table-hover">
    <thead className="thead-dark">
        <tr>
            <th>Description</th>
            {
                uniqueYears.map((value, key) => {
                    return <th key={key}>{value}</th>;
                })
            }
        </tr>
    </thead>
    <tbody className="table-hover">
        {element.Characteristics &&
            element.Characteristics.map((e, i) => {
                return (
                    <tr key={i}>
                        <td>{e.Description}</td>
                        {
                            uniqueYears.map((year, yearID) => {
                                if (e.Years.includes(year)) {
                                    return <td key={yearID}>Y</td>;
                                } else {
                                    return <td key={yearID}>N</td>;
                                }
                            })
                        }
                    </tr>
                );
            })}
    </tbody>
</table>