"Adds" two variant values together and returns the result
Description
mixedvariant_add
( mixed$left
, mixed$right
)
Adds left to right using
the following rules (taken from the MSDN library), which correspond to
those of Visual Basic:
Variant Addition Rules
If
Then
Both expressions are of the string type
Concatenation
One expression is a string type and the other a
character
Addition
One expression is numeric and the other is a string
Addition
Both expressions are numeric
Addition
Either expression is NULL
NULL is returned
Both expressions are empty
Integer subtype is returned
Parameters
left
The left operand.
right
The right operand.
Note:
As with all the variant arithmetic functions, the parameters for this function
can be either a PHP native type (integer, string, floating point, boolean or
NULL), or an instance of a COM, VARIANT or DOTNET class. PHP native types
will be converted to variants using the same rules as found in the constructor
for the VARIANT class. COM and DOTNET objects
will have the value of their default property taken and used as the variant value.
The variant arithmetic functions are wrappers around the similarly named
functions in the COM library; for more information on these functions, consult
the MSDN library. The PHP functions are named slightly differently; for example
variant_add in PHP corresponds to VarAdd()
in the MSDN documentation.