SizeOf

FreeBASIC

SizeOf
 
Returns the size of a variable or type in bytes.

Syntax

SizeOf ( variable | DataType )

Description

The SizeOf operator returns the number of bytes taken up by a variable or DataType.

Different from Len, when used with fixed-length strings (including fixed-length ZStrings and WStrings) it will return the number of bytes they use, and when used with variable-length strings, it will return the size of the string descriptor.

If there is both a user defined type and a variable visible with the same name in the current scope, the user defined type takes precedence over the variable. To ensure that the SizeOf takes the variable instead of the user defined type, wrap the argument to SizeOf with parentheses to force it to be seen as an expression. For example Sizeof((variable)).

Note: When used with arrays, SizeOf returns the size of a single element of the array. This differs from its behavior in C, where arrays could only be a fixed size, and sizeof() would return the number of it used.
For clarity, it is recommended that you avoid this potential confusion, and use SizeOf directly on an array element, rather than the whole array.

Remark: When used with a dereferenced z/wstring pointer, SizeOf always returns the number of bytes taken up by one z/wstring character (instead of 0 before fbc version 0.90).

Example

Print SizeOf(Byte) ' returns 1

Type bar
    a As Integer
    b As Double
End Type
Dim foo As bar
Print SizeOf(foo)



Dialect Differences

  • Not available in the -lang qb dialect unless referenced with the alias __Sizeof.

Differences from QB

  • New to FreeBASIC

See also