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JavaScript Introduction to Programming Control Structures If/Else

R R
R R
1,570 Points
Posted by R R
R R
1,570 Points

Why does the If block run even if I plug in a false-e value for my variable?

My "if block" runs if I plug in a name into the prompt just like it should. But, I assumed that the else block would run if i plugged in 0 or null into the prompt. But, the if block runs regardless. Is this because the code sees anything plugged into the prompt as a string/text rather than as code?

onsole.log("Before");

var name = prompt("What is your name?")
if (name) {
    console.log("if block")


} else {

    console.log("else block")

3 Answers

Geoff Parsons
Geoff Parsons
11,679 Points

prompt() will always return a string. So if you put 0 or null in you're going to get "0" or "null" back.

R R
R R
1,570 Points
R R
R R
1,570 Points

Thank you, Geoff. This noob appreciates the help. :-)

William Titterton
William Titterton
10,960 Points
William Titterton
William Titterton
10,960 Points

you can also return an integer from a prompt value using the 'parseInt(variable_name)' function

Matt Varner
Matt Varner
5,373 Points
Matt Varner
Matt Varner
5,373 Points

Hmm...I have to try that.