JavaScript String - charCodeAt() Method

Description

This method returns a number indicating the Unicode value of the character at the given index.

Unicode code points range from 0 to 1,114,111. The first 128 Unicode code points are a direct match of the ASCII character encoding. charCodeAt() always returns a value that is less than 65,536.

Syntax

Use the following syntax to find the character code at a particular index.

string.charCodeAt(index);

Argument Details

index − An integer between 0 and 1 less than the length of the string; if unspecified, defaults to 0.

Return Value

Returns a number indicating the Unicode value of the character at the given index. It returns NaN if the given index is not between 0 and 1 less than the length of the string.

Example

Try the following example.

Live Demo

<html>
   <head>
      <title>JavaScript String charCodeAt() Method</title>
   </head>
   
   <body>   
      <script type = "text/javascript">
         var str = new String( "This is string" );
         document.write("str.charCodeAt(0) is:" + str.charCodeAt(0)); 
         document.write("<br />str.charCodeAt(1) is:" + str.charCodeAt(1)); 
         document.write("<br />str.charCodeAt(2) is:" + str.charCodeAt(2)); 
         document.write("<br />str.charCodeAt(3) is:" + str.charCodeAt(3)); 
         document.write("<br />str.charCodeAt(4) is:" + str.charCodeAt(4)); 
         document.write("<br />str.charCodeAt(5) is:" + str.charCodeAt(5)); 
      </script>      
   </body>
</html>

Output

str.charCodeAt(0) is:84
str.charCodeAt(1) is:104
str.charCodeAt(2) is:105
str.charCodeAt(3) is:115
str.charCodeAt(4) is:32
str.charCodeAt(5) is:105

javascript_strings_object.htm