Len

Source: Positron16 Compiler User Manual, PDF page 363

Syntax

Assignment Variable = Len(Source String)

Overview

Find the length of a String. (not including the null terminator) .

Parameters

Source String can be a String variable, or a Quoted String of Characters. The Source String can also be a Byte, Word, Float or Array variable, in which case the value contained within the variable is used as a pointer to the start of the Source String's address in RAM. A third possibility for Source String is a label name, in which case a null terminated Quoted String of Characters is read from code memory. Assignment Variable is a user defined variable.

Example 1

' Display the length of SourceString
  Device = 24HJ128GP502
                                     ' Select the device to compile for
  Declare Xtal = 16
  Dim SourceString as String * 20  ' Create a String capable of 20 characters
  Dim Length as Byte
  SourceString = "Hello World"
                                     ' Load the source string with characters
  Length = Len(SourceString)
                                     ' Find the length of the String
  Print Dec Length
                                     ' Display the result, which will be 11

Example 2

' Display the length of a Quoted Character String
  Device = 24HJ128GP502
                                     ' Select the device to compile for
  Declare Xtal = 16
  Dim Length as Byte
  Length = Len("Hello World")
                                     ' Find the length of the String
  Print Dec Length
                                     ' Display the result, which will be 11

Example 3

' Display the length of SourceString using a pointer to SourceString
  Device = 24HJ128GP502
                                     ' Select the device to compile for
  Declare Xtal = 16
  Dim SourceString as String * 20  ' Create a String capable of 20 characters
  Dim Length as Byte
                                     ' Display the length of SourceString
  Dim SourceString as String * 20  ' Create a String capable of 20 characters
' Create a Word variable to hold the address of SourceString
  Dim StringAddr as Word
  SourceString = "Hello World"
                                     ' Load the source string with characters
  ' Locate the start address of SourceString in RAM
  StringAddr = AddressOf(SourceString)
  Length = Len(StringAddr)
                                     ' Find the length of the String
 Print Dec Length       ' Display the result, which will be 11

Example 4

' Display the length of a code memory string
  Device = 24HJ128GP502
                                     ' Select the device to compile for
  Declare Xtal = 16
  Dim Length as Byte
'
' Create a null terminated string of characters in code memory
'
  Dim Source as Code = "Hello World", 0
  Length = Len(Source)
                                     ' Find the length of the String
  Print Dec Length
                                     ' Display the result, which will be 11

Len