How to convert multiple dimension list into one dimension list

Question

If I have this JSON data that is from the original file.

[{"food": {"spicy": "spicy","sweet": "sweet"},
  "water": {"sweet": "sweet","sour": {"cold": "ice lemon","hot": "lemon tea"}}
}, {"food": {"spicy": "spicy","sweet": "sweet"},
  "water": {"sweet": "sweet","sour": {"cold": "ice lemon","hot": "lemon tea"}}
}]

how do I convert into a one-dimensional list like this?

[{
    "food-spicy": "spicy",
    "food-sweet ": "sweet",
    "water-sweet ": "sweet",
    "water-sour-cold ": "ice lemon",
    "water-sour-hot ": "lemon tea"
}, {
    "food-spicy": "spicy",
    "food-sweet ": "sweet",
    "water-sweet ": "sweet",
    "water-sour-cold ": "ice lemon",
    "water-sour-hot ": "lemon tea"
}]

Please help.

Answer 1

您可以编写一个递归展平对象的函数。然后使用该函数map数组：

function flatten(oldObj) {
    return Object.keys(oldObj).reduce(function(newObj, oldKey) {   // for each key "oldKey" in oldObj 
        var value = oldObj[oldKey];                                // get the value of the current oldKey from oldObj
        if(value && typeof(value) === "object") {                  // if the value is also an object (add "&& !Array.isArray(value)" to exclude arrays)
            value = flatten(value);                                // then flatten it first
            Object.keys(value).forEach(function(key) {             // and for each key in the new flattened value object
                newObj[oldKey + "-" + key] = value[key];           // add a key-value to newObj where key is "oldKey-key" and the value is value[key]
            });
        } else {
            newObj[oldKey] = value;                                // otherwise (if the value is not an object), just copy the key-value to newObj as it is
        }
        return newObj;
    }, {});
}

然后像这样使用它：

var newArray = oldArray.map(flatten);

示例：

＆＃13;

＆＃13;

function flatten(oldObj) {
    return Object.keys(oldObj).reduce(function(newObj, oldKey) {
        var value = oldObj[oldKey];
        if(value && typeof(value) === "object") {
            value = flatten(value);
            Object.keys(value).forEach(function(key) {
                newObj[oldKey + "-" + key] = value[key];
            });
        } else {
            newObj[oldKey] = value;
        }
        return newObj;
    }, {});
}



var oldArray = [{"food":{"spicy":"spicy","sweet":"sweet"},"water":{"sweet":"sweet","sour":{"cold":"ice lemon","hot":"lemon tea"}}},{"food":{"spicy":"spicy","sweet":"sweet"},"water":{"sweet":"sweet","sour":{"cold":"ice lemon","hot":"lemon tea"}}}];

var newArray = oldArray.map(flatten);

console.log(newArray);

＆＃13;

＆＃13;

＆＃13;

Answer 2

试试这个：

var data = [{
    food: {
      spicy: 'spicy',
      sweet: 'sweet'
    },
    water: {
      sweet: 'sweet',
      sour: {
        cold: 'ice lemon',
        hot: 'lemon tea'
      }
    }
  },
  {
    food: {
      spicy: 'spicy',
      sweet: 'sweet'
    },
    water: {
      sweet: 'sweet',
      sour: {
        cold: 'ice lemon',
        hot: 'lemon tea'
      }
    }
  }
]

var res = data.map(obj => {
  return Reflect.ownKeys(obj).reduce((re, key) => {
    Reflect.ownKeys(obj[key]).reduce((r, k) => {
      if (typeof obj[key][k] === 'object') {
        Reflect.ownKeys(obj[key][k]).reduce((r2, k2) => {
          r2[key + '-' + k + '-' + k2] = obj[key][k][k2]
          return r2
        }, r)
      } else {
        r[key + '-' + k] = obj[key][k]
        return r
      }
    }, re)
    return re
  }, {})
})
console.log(res)

这是一个更通用的版本，适用于更多嵌套的obj

var data = [{
    food: {
      spicy: 'spicy',
      sweet: 'sweet'
    },
    water: {
      sweet: 'sweet',
      sour: {
        cold: 'ice lemon',
        hot: 'lemon tea'
      }
    }
  },
  {
    food: {
      spicy: 'spicy',
      sweet: 'sweet'
    },
    water: {
      sweet: 'sweet',
      sour: {
        cold: 'ice lemon',
        hot: 'lemon tea'
      }
    }
  }
]

function customReduce(obj, subObj, lastReduceObj = {}, lastKey = '') {
  let res = Reflect.ownKeys(subObj).reduce((re, key) => {
    if (lastKey === '') {
      customReduce(obj, obj[key], re, key)
    } else if (typeof subObj[key] === 'object') {
      customReduce(obj, subObj[key], re, lastKey + '-' + key)
    } else {
      re[lastKey + '-' + key] = subObj[key]
    }
    return re
  }, lastReduceObj)
  return res
}

var res = data.map(obj => {
  return customReduce(obj, obj)
})

console.log(res)

Answer 3

试试这个：

var jsonObj = [{
	"food": {
		"spicy": "spicy",
		"sweet": "sweet"
	},
	"water": {
		"sweet": "sweet",
		"sour": {
			"cold": "ice lemon",
			"hot": "lemon tea"
		}
	}
}, {
	"food": {
		"spicy": "spicy",
		"sweet": "sweet"
	},
	"water": {
		"sweet": "sweet",
		"sour": {
			"cold": "ice lemon",
			"hot": "lemon tea"
		}
	}
}];

var newObj = {};

for (var i in jsonObj) {
  for (var j in Object.keys(jsonObj[i])) {
    for (var k in Object.keys(jsonObj[i])[j]) {
    newObj[Object.keys(jsonObj[i])[j]+'-'+Object.keys(jsonObj[i][Object.keys(jsonObj[i])[j]])[k]] = jsonObj[i][Object.keys(jsonObj[i])[j]][Object.keys(jsonObj[i][Object.keys(jsonObj[i])[j]])[k]];
    }
  }
}

console.log([flatJSON(newObj)]);

function flatJSON(obj) {
  if(typeof obj != 'object') {
    return;
  }
  for (var l in Object.keys(obj)) {
    if (typeof obj[Object.keys(obj)[l]] == 'object') {
      for (var m in Object.keys(obj[Object.keys(obj)[l]])) {
        newObj[Object.keys(obj)[l]+'-'+Object.keys(obj[Object.keys(obj)[l]])[m]] = obj[Object.keys(obj)[l]][Object.keys(obj[Object.keys(obj)[l]])[m]];
      }
    }
    if (typeof obj[Object.keys(obj)[l]] == 'object') {
      delete obj[Object.keys(obj)[l]];
    }
    if (obj[Object.keys(obj)[l]] === undefined) {
      delete obj[Object.keys(obj)[l]];
    }
  }
  return newObj;
}