How to return only non-null values ​of object properties in an object array?

To return only non-null values of object properties in an object array, you can use a combination of Array.prototype.map() and Object.entries(). Here's a step-by-step guide:

Assuming you have an array of objects like this:

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const data = [
  { id: 1, name: 'John', age: 25, address: null },
  { id: 2, name: 'Alice', age: null, address: '123 Main St' },
  { id: 3, name: null, age: 30, address: '456 Park Ave' },
  { id: 4, name: 'Bob', age: 35, address: '789 Elm St' },
];

Step 1: Use Array.prototype.map() to iterate over the array.

Step 2: For each object in the array, use Object.entries() to get an array of key-value pairs.

Step 3: Use Array.prototype.reduce() to filter out the non-null values.

Step 4: Create a new object with the filtered key-value pairs.

Step 5: Return the filtered object for each element in the resulting array.

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const filteredData = data.map((obj) => {
  return Object.entries(obj).reduce((acc, [key, value]) => {
    if (value !== null) {
      acc[key] = value;
    }
    return acc;
  }, {});
});

console.log(filteredData);

Output:

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[
  { id: 1, name: 'John', age: 25 },
  { id: 2, name: 'Alice', address: '123 Main St' },
  { id: 3, age: 30, address: '456 Park Ave' },
  { id: 4, name: 'Bob', age: 35, address: '789 Elm St' },
]

Now, filteredData contains the array of objects with only non-null values of object properties. It removes properties that have a value of null.