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JavaScript CharCodeAt

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The JavaScript CharCodeAt function is used to return the Unicode of the Character at a specified index position. The syntax of the JavaScript CharCodeAt function is

String_Object.CharCodeAt(Index_Position)

JavaScript ChartCodeAt Function returns the Unicode of the Character from String_Object at specified Index_Position. If we specify the Index position out of range, then the ChartCodeAt() Function returns NaN.

JavaScript CharCodeAt Example

The following set of examples help you understand the ChartCodeAt Function in JavaScript Programming language.

<!DOCTYPE html>
<html>
<head>
    <title> JavaScript CharCodeAt </title>
</head>
<body>
    <h1>JavaScript CharCodeAt </h1>
    <p id= "Content1">Content 1</p>
    <p id= "Content2">Content 3</p>
    <p id= "Content3">Content 2</p>
<script>
 var Str_Original = "Tutorial GateWay";
 var Str_Extracted = Str_Original.charCodeAt(9);
 var Str_Extracted1 = Str_Original.charCodeAt(Str_Original.length - 1);
 var Str_Extracted2 = Str_Original.charCodeAt(Str_Original.length);
    
 document.getElementById("Content1").innerHTML = "Charcter at Index position 9 = " + Str_Extracted;
 document.getElementById("Content2").innerHTML = "Charcter at Index position 15 = " + Str_Extracted1; 
 document.getElementById("Content3").innerHTML = "Charcter at Index position 16 = " + Str_Extracted2; 
</script>
</body>
</html>

OUTPUT

JavaScript CharCodeAt

ANALYSIS

The following JS charcodeat statement finds the Character Unicode at index position 9, and it will be G.

var Str_Extracted = Str_Original.charCodeAt(9);

NOTE: You should count the space as One Character in JS CharCodeAt.

In the next line, we are using the JavaScript len function to calculate the string length.

var Str_Extracted1 = Str_Original.charCodeAt(Str_Original.length - 1);

In the above statement, we are subtracting 1 from string length. Because the length of a Str_Original is 16, and there is no character at index position 16. Let us see, what will happen when we select 16 in JavaScript charcodeat

var Str_Extracted2 = Str_Original.charAt(Str_Original.length);

From the above screenshot, you can observe that it returned NaN.