How to Flatten JavaScript objects into a single-depth Object?

Javascript Web Development Front End Technology

In JavaScript, an object can be created by using curly braces {}. This is called an object literal. An object literal can contain properties and methods.

What is Flattening?

Flattening is the process of reducing an object to a single−depth object. In other words, all the properties and methods of the object are contained within a single−depth object.

How to Flatten an Object?

There are various ways to flatten an object.

Using for...in loop

The for...in loop can be used to iterate over the properties of an object. For each property, we can add it to a new object.

Below is the code snippet for flattening an object using the for...in loop.


<!doctype html>
<html>
<head>
   <title>Example - flatten an object</title>
</head>
<body>
   <div id="result1">Original Object: </div>
   <div id="result2">Flatten Object: </div>
   <script>
      var obj = {
         "a": 1,
         "b": 2,
         "c": {
            "d": 3,
            "e": 4
         }
      };
      var newObj = {};
      for (var key in obj) {
         if (typeof obj[key] === "object") {
            for (var subKey in obj[key]) {
               newObj[subKey] = obj[key][subKey];
            }
         } else {
            newObj[key] = obj[key];
         }
      }
      document.getElementById("result1").innerHTML += JSON.stringify(obj)
      document.getElementById("result2").innerHTML += JSON.stringify(newObj)
      console.log(newObj);

   </script>
</body>
</html>

In the above code, We have declared an object literal named obj. Then we have declared an empty object literal named newObj. We have used the for...in loop to iterate over the properties of obj. For each property, we have checked if the property value is an object. If the property value is an object, then we have again used the for...in loop to iterate over the sub−properties of the property value.

For each sub−property, we have added it to the newObj object with the sub−property name as the key. If the property value is not an object, then we have added the property to the newObj object with the property name as the key. Finally, we have logged newObj to the console.

Benefits of Flattening

There are various benefits of flattening an object. Some of them are−

Easy to Access Properties

When an object is flattened, all the properties and methods are contained within a single object. This makes it easy to access the properties and methods.

Easy to Manipulate Data

When an object is flattened, the data is contained within a single object. This makes it easy to manipulate the data.

Easy to Serialize

When an object is flattened, it can be easily serialized. Serialization is the process of converting an object to a format that can be stored or transmitted.

Disadvantages of Flattening

There are some disadvantages of flattening an object. Some of them are−

Data Redundancy

When an object is flattened, there is a possibility of data redundancy. Data redundancy is when the same data is stored in multiple places.

Difficulty in Maintaining

When an object is flattened, it can be difficult to maintain. This is because all the properties and methods are contained within a single object.

Conclusion

In conclusion, flattening is the process of reducing an object to a single−depth object. There are various ways to flatten an object. Some of the benefits of flattening an object are easy access to properties, easy manipulation of data, and easy serialization. There are some disadvantages of flattening an object such as data redundancy and difficulty in maintaining.