how to define a variable in an javascript ifstatement

Question

var x; 

function apply() {
    if (x = 1) {
        alert("show");
        document.getElementById("nav").style.display = "inline";
        var x = 2;
    } else {
        alert("hide");
        document.getElementById("nav").style.display = "none";
        var x = 1;
    }
}

function hide() {
    document.getElementById("nav").style.display = "none";
    x = 1;
    alert(x)
}

I am having some trouble with this piece of code. I use the function hide onload and have function apply linked to a button click.

the issue that im having is that when the code runs it hides the div on load and the shows it again on first button click and the i get stuck not being able to hide the div again — user3758155, Nov 25 '14 at 16:33

score 5 · Accepted Answer · answered Nov 25 '14 at 16:31

Correct usage:

var x; // we define the variable x global outside the functions

function apply() {
    if (x == 1) { // you need to check with ==, with = you are just setting its value
        alert("show")
        document.getElementById("nav").style.display = "inline";
        x = 2 // change the varibale to 2
    } else {
        alert("hide")
        document.getElementById("nav").style.display = "none";
        x = 1 // change it to 1
    }

}

function hide() {
    document.getElementById("nav").style.display = "none";
    x = 1;
    alert(x)
}

score 0 · Answer 2 · answered Nov 25 '14 at 16:34

0

You cant define both outside from if and inside of if. You should remove 'var' from inside of if

answered Nov 25 '14 at 16:34

Polat Dundar

76
9

You can, it's just that the one inside has a different scope. Its worth explaining fully, as a one line answer is rarely judged as good. – Jamiec Nov 25 '14 at 16:37

how to define a variable in an javascript ifstatement

2 Answers2