Returns the length of an expression or data type
Syntax
Usage
result = Len( expression )
or
result = Len( DataType )
Parameters
expression
An expression of any type.
datatype
Return Value
Returns the size of an expression or
DataType in bytes.
Description
Len returns the length of an expression or the size of a
DataType, in bytes.
In the first form, if
expression is of type
String,
WString or
ZString, the length of the string in characters will be returned. If the expression is of a user defined type, an
Operator Len compatible with that data type is called. Otherwise, the size of the
expression's data type in bytes is returned.
In the second form, if
expression is
ZString or
WString, the size in bytes of an ASCII or Unicode character is returned, respectively. If
datatype is
String, the size of the string descriptor type is returned.
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
Len takes the variable instead of the user defined type, wrap the argument to
Len with parentheses to force it to be seen as an expression. For example
Len((variable)).
The
Len unary
Operator can be overloaded with user defined types.
Example
Print Len("hello world") 'returns "11"
Print Len(Integer) ' returns 4
Type xyz
a As Integer
b As Integer
End Type
Print Len(xyz) ' returns 8
Dialect Differences
- Len only allows expressions in the -lang qb dialect.
- Can be used with built-in types and user-defined types in the -lang fb and -lang fblite dialects.
Differences from QB
See also