By Microsoft Team

 

Summary: in this tutorial, you will learn about the TypeScript break statement to terminate a loop or a switch. 

 

Using TypeScript break to terminate a loop 

 

The break statement allows you to terminate a loop and pass the program control over the next statement after the loop. 

 

You can use the break statement inside the for, while, and do...while statement. 

 

The following example shows how to use the break statement inside a for loop:

 

let products = [
    { name: 'phone', price: 700 },
    { name: 'tablet', price: 900 },
    { name: 'laptop', price: 1200 }
];

for (var i = 0; i < products.length; i++) {
    if (products[i].price == 900)
        break;
}

// show the products
console.log(products[i]);

 

Output:

 

{ name: 'tablet', price: 900 }

 

How it works: 

 

First, initialize a list of products with name and price properties. 

Then, search for the product whose price is 900 and terminate the loop once the product is found by using the break statement. 

Finally, show the matching product to the console. 

 

Using the break statement to break a switch 

 

The following example returns the discount of a specified product. It uses the break statement to break out of a switch:

 

let products = [
    { name: 'phone', price: 700 },
    { name: 'tablet', price: 900 },
    { name: 'laptop', price: 1200 }
];

let discount = 0;
let product = products[1];

switch (product.name) {
    case 'phone':
        discount = 5;
        break;
    case 'tablet':
        discount = 10;
        break;
    case 'laptop':
        discount = 15;
        break;
}

console.log(`There is a ${discount}% on ${product.name}.`);

 

Note that besides a loop or a switch, the break statement can be used to break out of a labeled statement. However, it is rarely used in practice so that we don’t cover in this tutorial.

 

Summary 

 

  • Use break statement to terminate a loop or switch.