how can we declare a variable globally to use it in different script

Question

how can we declare a variable globally so that we can use it in different different scripts written within same page.In below code how can i declare variable globally in script 1 so that i can used it in script 2.

.php page

 <!DOCTYPE HTML>
 <html>
  <head>
  <script type="text/javascript">
   //this is first script//
   </script >
  <script type="text/javascript">
   //this is second script//
   </script >
  </head>
 </html>

yes i did but nothing happened, that variable is working within that script only. — Archana Gupta, Jul 13 '17 at 12:09
Duplicate. See your answers here: https://stackoverflow.com/questions/2932782/global-variables-in-javascript-across-multiple-files — Ezis, Jul 13 '17 at 12:09
no i dont want it from different file .i want to do within same file but 2 different script .can it be possible?@HassanImam — Archana Gupta, Jul 13 '17 at 12:10
Maybe because you haven't declared any variable. The global scope is shared with all the scripts in the document, and all global variables are available in all scripts as well. — Teemu, Jul 13 '17 at 12:13

prasanth · Answer 1 · 2017-07-13T12:18:21.467

1

You need to properly closing the script tag .and declare the var in first one then access with below script .

Order of the script is more important.

if you add some other js link to handle var a.add this new link below the first one

Updated

1.defined variable validation and replace the global varibale

<!DOCTYPE HTML>
 <html>
  <head>
  <script type="text/javascript">
   //this is first script//
   var a ="hi"
   </script>
  <script type="text/javascript">
   //this is second script//
   if(typeof a !== "undefined") { // for defined varibale validation
   console.log(a)
   a='hello' // replaced
   console.log(a)
   }
   </script>
  </head>
 </html>

edited Jul 13 '17 at 12:18

answered Jul 13 '17 at 12:08

prasanth

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If you want to be sure that the variable is already init, you can check it with null test and init it else. – Kashkain Jul 13 '17 at 12:10
like if create var a="" in one script and then in second script can i assign a value to that 'a' variable? – Archana Gupta Jul 13 '17 at 12:13
@ArchanaGupta Note that last assign value are in your variable. – Jaykumar Gondaliya Jul 13 '17 at 12:20

score 0 · Answer 2 · answered Jul 13 '17 at 12:13

i suggest you to create one file for global variable like 1st glob.js

and Code like

<script type="text/javascript">
   //this is GLOBAL script//
   var a ="MY_FRIST_VAR"
   </script>

and used it as

<script type="text/javascript" src="glob.js"></script>
 <script>
console.log(a)
<script>

how can we declare a variable globally to use it in different script

2 Answers2