This content originally appeared on DEV Community and was authored by Dharshini E
1.what is function?
set of instruction perform specific task can be called multiple times optionally takes input as** parametters** and optionally returns values.
Functions significantly enhance code reusability by encapsulating specific functionalities into self-contained blocks.
This allows the same block of code to be invoked **multiple times **from different parts of a program.
function is a keyword.
syntax:
function functionName(parameter1, parameter2, ...) {
return value; // Optional return statement
}
functionName() -function calling statement
{ } – function definition
.log() – is a function , its created by javascript perdefined functions or inbuilt funtion.
example :
console.log("welcome!");
typeof – its used to find “which type of data is given”.
example:
let name ="dharshini";
console.log(typeof name);
BigInt – datatype
BigInt variables are used to store big integer values that are too big to be represented by a normal JavaScript Number.
example:
let y = 9999999999999999n;
What is return ?
The return statement stops the execution of a function and returns a value.
function myFunction(name) {
return "Hello " + name;
}
console.log(myFunction("dharshini")); // Hello dharshini
prompt()
In JavaScript, the prompt() method is a built-in function used to display a dialog box that prompts the user for input. This dialog box includes a message, a text input field, and “OK” and “Cancel” buttons.
Syntax :
result = prompt(message, defaultValue);
alter()
In JavaScript, alert() is a global function used to display a modal dialog box with a specified message and an “OK” button. This dialog box pauses the execution of the script until the user clicks “OK”.
example:
alert(" please enter vaild input");
happy codding!
This content originally appeared on DEV Community and was authored by Dharshini E