byteLength

Description

Returns the number of bytes required to represent a UTF-8 encoded string.

Syntax

Like many functions in DataPrime, byteLength supports two notations, function and method. These interchangeable forms allow flexibility in how you structure expressions.

Function notation

byteLength(value: string): number

Method notation

(value: string).byteLength(): number

Arguments

Name	Type	Required	Description
value	string	true	The string to measure in UTF-8 bytes

Example

Compare character count vs. byte count for a UTF-8 encoded string

Consider the following document:

{
    "time_taken_str": "100μs"
}

Using length returns the number of characters:

create len from time_taken_str.length()

This produces:

{
    "time_taken_str": "100μs",
    "len": 5
}

However, this does not reflect the true byte size. The character μ requires two bytes in UTF-8.

Example query

Function notation

create byte_len from byteLength(time_taken_str)

Method notation

create byte_len from time_taken_str.byteLength()

Example output

{
    "time_taken_str": "100μs",
    "byte_len": 6
}

The four ASCII characters (1, 0, 0, s) each take one byte, and the μ symbol takes two bytes, for a total of six.