Dynamically change and check variable in javascript

Question

I have the following code:

JS:

var flag = 0;
funct(){//makes changes on css
flag=0;}

HTML:

<form onsubmit="if(flag==1)return funct()">

PHP:

if(somethingIsOK){
    echo "<script>flag=1;</script>"; //should use new css which comes with funct()
}else{//do something else with keeping the existing css}

I want this structure, but I could not use the variable flag like I wanted to. I have tried making flag static but it did not work.

Answer 1

Use the hidden field to set/unset flag

<input type="hidden" name="flag" id="flag" value="1" />

javascript

var flag = document.getElementById('flag').value;
funct(){//makes changes on css
document.getElementById('flag').value=0;
}

Answer 2

I don't like the way you do it, but the answer is to delete var before flag to make it global:

flag = 0;

proof

EDIT

1. if you want to prevent form submit your funct() must return false;

2. maybe you try

    if(somethingIsOK){ echo "<script type="text/javascript">flag=1;</script>"; }else{ echo "<script type="text/javascript">flag=0;</script>"; } 

and again: it's a very-very bad idea to mix php and JS like that

Answer 3

You can't easily use the same variable in both PHP and JS. What you can do however is make a <input type="hidden"> with the name flag and the value of the variable and then read it in both PHP and JS.

Answer 4

Its bad idea to use constructions like this, but if you realy want use some global variable you can assign it to window object property, ie:

window.flag = 0;

And use this variable(window.flag) everywhere you need it.

Answer 5

var flag = 0;
funct(){//makes changes on css
flag=0;}

try

var flag = 0;
function funct(){  // <<<<< function
//makes changes on css
flag=0;}