Question

我有一个嵌套的json，其中包含带有布尔值的检查键。我只想为那些在结果数组中具有true的名称键值。

示例JSON

 const treeMetaData = [
{
  name  :  'database',
  checked : true,
  schemas  : [
    {
      name  : "schema1",
      checked : true,
      tables : [
        {
          name  : "table1",
          checked : true,
          columns : [
            {
              name  : "column1",
              checked : false,
            }, 
            {
              name  : "column2",
              checked : true,
            }
          ]
        },
      ]
    },
    {
      name  : "schema2",
      checked : true,
      tables : [
        {
          name  : "table2",
          checked : true,
          columns : [
            {
              name  : "column4",
              checked : true,
            }, 
            {
              name  : "column5",
              checked : false,
            }
          ]
        },
      ]
    },

  ]
}]

我需要的输出

 ["database", "schema1", "table1", "column2", "schema2", "table2", "column4"]

确实需要帮助，并希望采用优化的方法，因为此树数据的大小很大。

Answer 1

似乎很简单，您是否尝试编写一些循环？

var result = [];

treeMetaData.forEach(database => {
    if(!database.checked){ return; }
    result.push(database.name);
    database.schemas.forEach(schema => {
        if(!schema.checked){ return; }
        result.push(schema.name);
        schema.tables.forEach(table => {
            if(!table.checked){ return; }
            result.push(table.name);
            table.columns.forEach(column => {
                if(!column.checked){ return; };
                result.push(column.name);               
            });         
        });     
    });
});

//result is now: ["database", "schema1", "table1", "column2", "schema2", "table2", "column4"]

Answer 2

您可以使用递归，并获取具有数组值的属性，以便知道要递归到的位置：

const listNames = arr =>
    arr.filter(({checked}) => checked).map(obj => {
        let val = Object.values(obj).find(val => Array.isArray(val));
        return [obj.name].concat(val ? listNames(val) : []);
    }).flat()

const treeMetaData = [{name  :  'database',checked : true,schemas  : [{name  : "schema1",checked : true,tables : [{name  : "table1",checked : true,columns : [{name  : "column1",checked : false,},{name  : "column2",checked : true,}]},]},{name  : "schema2",checked : true,tables : [{name  : "table2",checked : true,columns : [{name  : "column4",checked : true,},{name  : "column5",checked : false,}]},]},]}];
let res = listNames(treeMetaData);
console.log(res);

Answer 3

嵌套就是答案

const treeMetaData = [
{
  name  :  'database',
  checked : true,
  schemas  : [
    {
      name  : "schema1",
      checked : true,
      tables : [
        {
          name  : "table1",
          checked : true,
          columns : [
            {
              name  : "column1",
              checked : false,
            }, 
            {
              name  : "column2",
              checked : true,
            }
          ]
        },
      ]
    },
    {
      name  : "schema2",
      checked : true,
      tables : [
        {
          name  : "table2",
          checked : true,
          columns : [
            {
              name  : "column4",
              checked : true,
            }, 
            {
              name  : "column5",
              checked : false,
            }
          ]
        },
      ]
    },

  ]
}]

const result = []

treeMetaData.forEach(item => {
  if(item['checked']){
    result.push(item['name'])
    let schemas = item['schemas']
    schemas.forEach(schema => {
       if(item['checked']){
        result.push(schema['name'])
        let tables = schema['tables']
        tables.forEach(table => {
          if(table['checked']){
            result.push(table['name'])
            let columns = table['columns']
            columns.forEach(column => {
              if(column['checked']){
                result.push(column['name'])
              }
            });
          
          }
        });
       }
    });
    
  }
});

console.log(result)

如何从嵌套的JSON对象获取检查值的数组

3 个答案: