JavaScript Scopes, Easy to Learn JavaScript Scopes

JavaScript scopes

In JavaScript scope defines accessibility of variables, objects and functions.

There are two types of scope in JavaScript.

1. Global scope

2. Local scope

Global Scope :

Global Scope is nothing but a window level scope. Here, Global variable present throughout the application

Example :

<html>
<head>
<title>Javascript Global Variables</title>
</head>
<body>
 
<h4 id="web_site"></h4>
 
<script type="text/javascript">

  var website = "www.freetimelearning.com";
  myFunction();
  function myFunction() {
  document.getElementById("web_site").innerHTML =
  "This is our website : " + website;
  }

</script>
      
</body>
</html>

Output :

This is our website : www.freetimelearning.com

Local Scope :

Variables declared within a JavaScript function, become LOCAL to the function. Local variables cannot be accessed or modified outside the function declaration.

Example :

<html>
<head>
<title>Javascript Local Variables</title>
</head>
<body>
 
<h4 id="local_scope"></h4>
 
<script type="text/javascript">

myFunction();
document.getElementById("local_scope").innerHTML =
"Our website is " + typeof website;
 
function myFunction() {
    var website = "www.freetimelearning.com";
}

</script>
 
</body>
</html>

Output :

Our website is undefined

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