Question

我是Java语言的新手，正在尝试遍历一个嵌套的对象数组，并根据第一个对象的属性过滤第二个对象数组。

这都是数组的结构：

const displayArr = {
   sections: {
      section_1: [
        {
          style: "single_select_cmp",
          definition: {
            table_name: "table_1",
            field_name: "organization",
          }
        },
      ],
      section_2: [
        {
          style: "single_select_cmp",
          definition: {
            table_name: "table_1",
            field_name: "title",
          }
        },
      ]
   }
};

const schemaArr = [
  {
    table_1: {
      columns: [
        {
          description: "Tracking Number Desc",
          display_name: "Tracking Number",
          display_type: "number",
          field: "tracking_number",
          type: "int"
        },
        {
          description: "Title Desc",
          display_name: "Title",
          display_type: "multiple lines of text",
          field: "title",
          type: "text"
        },
        {
          description: "Description Desc",
          display_name: "Description",
          display_type: "multiple lines of text",
          field: "description",
          type: "text"
        },
        {
          description: "Organization Desc",
          display_name: "Organization",
          display_type: "single line of text",
          field: "organization",
          type: "text"
        }
     ]
   }
 },
 {
  table_2: { columns: [ {...}, {...} ] }
 },
 {
  table_3: { columns: [ {...}, {...} ] }
 }
 ...
]

我正在尝试按schemaArr中的table_name和field_name过滤displayArr。如果存在匹配项，我想向displayArr提供description和display_name。例如：

const displayArr = {
   sections: {
      section_1: [
        {
          style: "single_select_cmp",
          definition: {
            table_name: "table_1",
            field_name: "organization",
            description: "Organization Description", //***
            display_name: "Organization" //***
          }
        },
      ],
      section_2: [
        {
          style: "single_select_cmp",
          definition: {
            table_name: "table_1",
            field_name: "title",
            description: "Title Description", //***
            display_name: "Title" //***
          }
        },
      ]
   }
};

在此示例中，我只是从table_1中提取，但是displayArr中可能引用了许多表。

对我来说，鉴于这些对象是嵌套的，因此这是一种更为复杂的映射/过滤情况。我想知道如何正确有效地利用地图，过滤器和/或forEach。

预先感谢您的帮助！真的很感激。

Answer 1

Object.values()可用于获取displayArr对象的值，而forEach()可用于对其进行迭代。

find()方法可用于在table_name中以schemaArr查找表。如果存在表，则可以再次使用find()方法来查找包含项目的field_name的列。

然后displayArr对象的定义项可以使用找到的此列值进行更新。

Object.values(displayArr.sections).forEach(section => {
  section.forEach(item => {
    let table = schemaArr.find(table => table[item.definition.table_name]);

    if (table) {
      // Find column by field_name.
      let obj = table[item.definition.table_name].columns.find(column => column.field === item.definition.field_name);           

      if (obj) {
        // Update definition.
        item.definition.description = obj.description;
        item.definition.display_name = obj.display_name;
      }
    }
  });
});

遍历嵌套的对象数组，与另一个对象数组匹配

1 个答案: