Check if Array contains Empty String in JavaScript

Check if Array contains Empty String #

To check if an array contains an empty string, call the includes() method passing it an empty string - includes(''). The includes method returns true if the provided value is contained in the array and false otherwise.

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const arr = ['a', '', 'c'];

const result = arr.includes('');
console.log(result); // 👉️ true

We use the Array.includes method to check if the array contains an empty string.

The parameter we pass to the method is the value to search for in the array.

The includes method returns true if it finds the value in the array and false if it doesn't.

To check if an array contains an empty string:

1. Call the some() method, passing it a function.
2. On each iteration, check if the current element is equal to an empty string and return true if the condition is met.
3. The some method returns true if the provided function returns true at least once.

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// supported in IE

const arr = ['a', '', 'c'];

const result = arr.some(element => {
  if (element === '') {
    return true;
  }
});

console.log(result); // 👉️ true

The function we pass to the Array.some method gets called with each element in the array until it returns true, or iterates over the entire array.

We check if the current element's value is equal to an empty string and return true if it is.

If the function returns true at least once, the some method short-circuits and also returns true.

This is good for performance, because we don't have to keep iterating after we've found the answer.

This solution is not as elegant as the includes method, however if you have to support Internet Explorer, it gets the job done.

Further Reading #

• Check if all Values in Array are Equal in JavaScript
• Check if Array contains Empty Elements in JavaScript