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.

I assume the first part of the code is Javascript. Is this right? — lazyCrab
– lazyCrab, Commented Jul 16, 2013 at 7:20
Post your html + js on jsfiddle.net and update your question. — Konrad Gadzina
– Konrad Gadzina, Commented Jul 16, 2013 at 7:20
Dynamically change and check what variable? What condition? What is it you're trying to do? And post your (relevant/sscce) HTML here, not just at JS Fiddle. — David Thomas
– David Thomas, Commented Jul 16, 2013 at 7:21
I am sorry guys all are js, just if else parts are php, yes first part is js — user2586173
– user2586173, Commented Jul 16, 2013 at 7:22

coder · Accepted Answer · 2013-07-16 09:14:39Z

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;
}

answered Jul 16, 2013 at 9:14

coder

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Comments

lazyCrab · Accepted Answer · 2013-07-16 07:23:00Z

0

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.

answered Jul 16, 2013 at 7:23

lazyCrab

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Comments

Matyunin · Accepted Answer · 2013-07-16 07:23:01Z

0

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, i.e.:

window.flag = 0;

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

answered Jul 16, 2013 at 7:23

Matyunin

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3 Comments

lazyCrab Over a year ago

You are missing the point. The second part is in PHP while the first is in JS.

Matyunin Over a year ago

It doesn't matter, all js parts will be parsed after php.

Matyunin Over a year ago

Topicstarter doesn't used flag in php, he used it only in JS parts, no hidden field needed.

vladkras · Accepted Answer · 2013-07-16 09:03:06Z

0

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

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

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

edited Jul 16, 2013 at 9:03

answered Jul 16, 2013 at 7:22

vladkras

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Comments

JOE LEE · Accepted Answer · 2013-07-16 10:11:51Z

0

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

try

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

answered Jul 16, 2013 at 10:11

JOE LEE

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