This is a basic question about javascript as I am new I would like to try out different things as I used to do in C. So now my Question is when I use
console.log(alert())
I get the result undefined
. Do these functions return no values? If they return values what are those and why I can't check them in the console. Any help is appreciated.
Each function in JavaScript returns a value. If you haven't provided an explicit one, it returns undefined
. So alert
works and its returned value which is undefined
is passed to the console.log
.
Check this.
function foo() { } let result = foo(); console.log(result);
alert
always returns undefined
, as does console.log
.
If you wanted to save the input from the user in a variable, use prompt
:
const str = prompt('Input something'); console.log('str is', str);
(Or, even better, use a proper modal instead - alert
, prompt
and confirm
are all considered poor practice because they block )
alert(message);
This shows a message and pauses script execution until the user presses “OK”. it means it expect a string to be pass as a parameter which will be displayed in the prompts
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