CODESYS LEFT

LEFT is a string function that returns a specified number of characters from the start of a string. It takes a STRING(255) input and an INT size, and returns a STRING(255); LEFT('SUSI',3) returns 'SUS'.

Source checked9/9 values · 2026-10-26

Specification

2 sources

Language	iec 61131 3
Code	LEFT
Group	String Functions
Syntax	LEFT (STR, SIZE)
Dialect	CODESYS

Parameters

Name	Data type	Description
STR	STRING(255)	String to be analyzed
SIZE	INT	Number of characters

Study notes

The function declaration is FUNCTION LEFT : STRING(255).
The return value is a STRING(255) resulting string.
Example: VarSTRING1 := LEFT('SUSI',3); the result is 'SUS'.