VB & VBA in a Nutshell: The Language

Len, LenB Functions

Syntax

Len(string | varname)

string

Use: Required

Data Type: String

A valid string expression.

varname

Use: Required

Data Type: Any except object

A valid variable name.

Return Value

A Long integer

Description

Counts the number of characters within a string or the size of a given variable. Use LenB to determine the actual number of bytes required to hold a given variable in memory.

Rules at a Glance

• string and varname are mutually exclusive; that is, you must specify either string or varname, but not both.

• If either string or varname contains Null, Len returns Null.

• Len returns the size (number of characters) that a user-defined type occupies when written to a file.

• LenB returns the actual size of a user-defined type in memory.

• When you use LenB with byte data or a Unicode string, LenB returns the number of bytes that represent the data or the string.

• You can't use Len with an object variable.

• If varname is an array, you must also specify a valid subscript. In other words, Len can't determine the total number of elements in or the total size of an array.

Programming Tips and Gotchas

• When you use a random access file to store data and a user-defined type to handle that data within your application, you can use Len to determine the value of the Len = clause of the file's Open statement. However, if you have used variable length strings within your user-defined type, Len may not accurately determine the actual storage requirement of the user-defined type. For ...