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目录

JavaScript String charCodeAt()

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Examples

Get the Unicode of the first character in a string:

let text = "HELLO WORLD";
let code = text.charCodeAt(0);
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Get the Unicode of the second:

let text = "HELLO WORLD";
let code = text.charCodeAt(1);
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More examples below.

Description

The charCodeAt() method returns the Unicode of the character at a specified index (position) in a string.

The index of the first character is 0, the second is 1, ....

The index of the last character is string length - 1 (See Examples below).

See also the charAt() method.

See Also:

The charAt() Method

The codePointAt() Method

The indexOf() Method

The lastIndexOf() Method

charCodeAt() vs codePointAt()

charCodeAt() is UTF-16, codePointAt() is Unicode.

charCodeAt() returns a number between 0 and 65535.

Both methods return an integer representing the UTF-16 code of a character, but only codePointAt() can return the full value of a Unicode value greather 0xFFFF (65535).

For more information about Unicode Character Sets, visit our Unicode Reference.

Syntax

string.charCodeAt( index)

Parameters

Parameter Description
index Optional. A number.
The index (position) of a character.
Default value = 0.

Return Value

Type Description
A number The Unicode of the character at the specified index.
NaN if the index is invalid.

More Examples

Get the Unicode of the last character in a string:

let text = "HELLO WORLD";
let code = text.charCodeAt(text.length-1);
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Get the Unicode of the 15th character:

let text = "HELLO WORLD";
let code = text.charCodeAt(15);
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Related Pages

JavaScript Strings

JavaScript String Methods

JavaScript String Search

Browser Support

charCodeAt() is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes Yes
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