You can get the size of an array in TypeScript by using the length property. The length property returns the number of elements in the array.
Here is an example:
let numbers: number[] = [1, 2, 3, 4, 5];
console.log(numbers.length); // Output: 5
In the example above, we have an array of 5 numbers. We use the length property to get the size of the array which is 5.
You can also get the size of a string using the length property. Here is an example:
let name: string = "John";
console.log(name.length); // Output: 4
In the example above, we have a string with 4 characters. We use the length property to get the size of the string which is 4.