JavaScript String codePointAt() Method

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The JavaScript String codePointAt() method returns a non-negative integer value that represents the Unicode point of the character in the string starting at the specified index. If the given index is not within the range of 0 to str.length-1, the method returns "undefined" as a result.

This method returns the Unicode point value for both string characters and icons (emojis, symbols, etc.).

Syntax

Following is the syntax of JavaScript String codePointAt() method −

codePointAt(index)

Parameters

This method accepts a parameter named 'index', which is described below −

  • index − The zero-based index(position) of the character is to be returned.

Return value

This method returns a non-negative integer representing the uni code point value of the character at the given index.

Example 1

Retrieve the Unicode point of the first character in the string by passing the index value as 0.

In the following example, we are using the JavaScript String codePointAt() method to retrieve the Uni code point value of the character in the given string "Tutorials Point" at the specified index 0.

<html>
<head>
<title>JavaScript String codePointAt() Method</title>
</head>
<body>
<script>
   const str = "Tutorials Point";
   document.write("String: ", str);
   const index = 0;
   document.write("<br>Index: ", index);
   document.write("<br>The Uni code point value of the first character '", str.at(index), "' is: ", str.codePointAt(index));
</script>
</body>
</html>

Output

The above program returns the Uni code point value as 84 of the first character 'T' of the string "Tutorials Point".

String: Tutorials Point
Index: 0
The Uni code point value of the first character 'T' is: 84

Example 2

Retrieve the Unicode point of the last character in the string.

The following is another example of the JavaScript String codePointAt() method. We use this method to retrieve the Uni code point of character in the given string "Hello World" at the specified index str.length-1, which is the last element.

<html>
<head>
<title>JavaScript String codePointAt() Method</title>
</head>
<body>
<script>
   const str = "Hello World";
   document.write("String: ", str);
   const index = str.length-1;
   document.write("<br>Index: ", index);
   document.write("<br>The Uni code point value of the last character '", str.at(-1), "' is: ", str.codePointAt(index));
</script>
</body>
</html>

Output

After executing the above program, it will return uni code value of character 'd' as 100.

String: Hello World
Index: 10
The Uni code point value of the last character 'd' is: 100

Example 3

If the index parameter value is not in the range of 0 to str.length-1, it will return undefined.

In this example, we use the JavaScript String codePointAt() method to retrieve a uni code point of a character in the string "JavaScript" at the specified index -3, which is out of the range of 0 - str.length-1.

<html>
<head>
<title>JavaScript String codePointAt() Method</title>
</head>
<body>
<script>
   const str = "JavaScript";
   document.write("String: ", str);
   const index = -3;
   document.write("<br>Index: ", index);
   document.write("<br>The Uni code point value of character the specified index ", index, " is: ", str.codePointAt(index));
</script>
</body>
</html>

Output

Once the above program is executed, it will return "undefined".

String: JavaScript
Index: -3
The Uni code point value of character the specified index -3 is: undefined

Example 4

The Unicode code point value of icons (emojis).

In this program, the codePointAt() method is used to retrieve the Unicode point value of the icons.

<html>
<head>
<title>JavaScript String codePointAt() Method</title>
</head>
<body>
<script>
   document.write("Character(icon): ", "😀", ", Uni code point: ", "😀".codePointAt(0));
</script>
</body>
</html>

Output

The above program returns the Uni code point of the icon "😀" as "128512" −

Character(icon): 😀, Uni code point: 128512

Example 5

In the given program, we are using the codePointAt() method within the for-loop to retrieve the uni code point of all the characters present in the string "Welcome to Tutorials Point".

<html>
<head>
<title>JavaScript String codePointAt() Method</title>
</head>
<body>
<script>
   const str = "Welcome to Tutorials Point";
   document.write("String: ", str);
   document.write("<br>Uni code point value of all characters:<br>")
   for(let i = 0; i<str.length; i++){
      document.write("Character: ", str.at(i), ", Uni code point: ", str.charCodeAt(i), "<br>");
   }
</script>
</body>
</html>

Output

The above programs returns the uni code point of all characters: 

String: Welcome to Tutorials Point
Uni code point value of all characters:
Character: W, Uni code point: 87
Character: e, Uni code point: 101
Character: l, Uni code point: 108
Character: c, Uni code point: 99
Character: o, Uni code point: 111
Character: m, Uni code point: 109
Character: e, Uni code point: 101
Character: , Uni code point: 32
Character: t, Uni code point: 116
Character: o, Uni code point: 111
Character: , Uni code point: 32
Character: T, Uni code point: 84
Character: u, Uni code point: 117
Character: t, Uni code point: 116
Character: o, Uni code point: 111
Character: r, Uni code point: 114
Character: i, Uni code point: 105
Character: a, Uni code point: 97
Character: l, Uni code point: 108
Character: s, Uni code point: 115
Character: , Uni code point: 32
Character: P, Uni code point: 80
Character: o, Uni code point: 111
Character: i, Uni code point: 105
Character: n, Uni code point: 110
Character: t, Uni code point: 116
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