How to use Array.prototype.every() In Typescript
This approach utilizes the every() method to check if every element in the array is unique. It compares each element of the array with every other element to determine if there are any duplicates.
Syntax:
function hasDuplicatesUsingEvery(array: any[]): boolean {
return array.every((item, index) =>
array.indexOf(item) === index
);
}
Example: The following code demonstrates the use of the hasDuplicatesUsingEvery function to check for duplicates in an array.
function hasDuplicatesUsingEvery(array: any[]): boolean {
return array.every((item, index) =>
array.indexOf(item) === index
);
}
console.log(hasDuplicatesUsingEvery([1, 2, 3, 4, 5])); // Output: true
console.log(hasDuplicatesUsingEvery([1, 2, 3, 4, 1])); // Output: false
console.log(hasDuplicatesUsingEvery(["GFG", "JavaScript", "GFG"])); // Output: false
console.log(hasDuplicatesUsingEvery(["GFG", "JavaScript"])); // Output: true
Output:
true
false
false
true
How to Create a TypeScript Function to Check for Duplicates in an Array ?
We are given a TypeScript array and we have to create a TypeScript function that checks whether the given array contains duplicates or not.
Example:
Input: array1 = [1, 2, 3, 4, 5] Output: False Explantion: No duplicates in the array Input: array1 = [1, 2, 3, 4, 1] Output: True Explantion: 1 repeats two time in the array
Table of Content
- Using a Set to Create the Function
- Using Array.prototype.includes()
- Using Array.prototype.reduce()
- Using Array.prototype.every()