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What is a variant data type?
A Variant is a special data type that can contain any kind of data except fixed-length String data. (Variant types now support user-defined types.) A Variant can also contain the special values Empty, Error, Nothing, and Null.
Does C# have a variant type?
C# Variant data type A class that mimics the behavior of the so-called variant data type. The Variant class can be transparently assigned and converted to/from any basic data type (string, datetime, sbyte, byte, short, int, long, ushort, uint, ulong, float, double, bool, char, decimal as well as their nullable types).
What is Variant data type in Visual Basic?
The variant data type can be used to define variables that contain any type of data. A tag is stored with the variant data to identify the type of data that it currently contains. You can examine the tag by using the VarType function.
What are variant variables?
A Variant Variable can hold any time of data (string, integers, decimals, objects, etc.). If you don’t declare a variable type, your variable will be considered variant. To declare an Variant variable, you use the Dim Statement (short for Dimension): 1. Dim varName as Variant.
What is Variant data type give an example?
In Visual Basic (and Visual Basic for Applications) the Variant data type is a tagged union that can be used to represent any other data type (for example, integer, floating-point, single- and double-precision, object, etc.) except fixed-length string type.
What is difference between string and variant?
The variant has a special sub type called string-variant that can be used to hold variable-length strings. This data type uses 22 bytes plus the length of the string. This data type is much larger than a normal variable-length string. The string-variant data type can contain the same as a variable-length string.
What is a variant in C#?
A variant, or discriminated union type [1], is a type that can hold a value of any of a finite set of types. For example, a Variant can hold either an int or a string value. This is also known as a sum type, as its domain is the sum of the int and string domains.
What is dynamic type in C#?
C# 4 introduces a new type, dynamic . The type is a static type, but an object of type dynamic bypasses static type checking. In most cases, it functions like it has type object . At compile time, an element that is typed as dynamic is assumed to support any operation. Therefore, no compiler error is reported.
What is difference between string and Variant?
Which of these is disadvantage of Variant data type?
The disadvantages are that certain pieces of code using variant may process a little more slowly than others, or may not catch certain classes of programming errors. The default data type is variant. Variant is a self-describing data type that can hold simple numeric or string values.
What is the size of Variant data type *?
The Variant data type has a numeric storage size of 16 bytes and can contain data up to the range of a Decimal, or a character storage size of 22 bytes (plus string length),and can store any character text.
Can a variant be a string?
Variables declared as the Variant data type can contain string, date, time, Boolean, or numeric values, and can convert the values that they contain automatically. String Variant values require 22 bytes of memory.
How are variant datatypes used in the C language?
C is a very strong typed language, variants are not part of its philosophy. An union can’t be a solution because you still have to choose the data type you want to use, it’s typically used to store color codes on int and char [4]. Data types are represented by char* and it’s the developer’s task to figure how to get types from these.
How to convert variant data type to C #?
So, rather than worry about passing the VARIANT to C#, look at the variant data type and convert it in C++ to the actual data type and pass that to C#. For example, if the VARIANT type is VT_INT, then get the int from the variant and can use something like:
What is the variant data type in Excel?
Variant data type. The Variant data type is the data type for all variables that are not explicitly declared as some other type (using statements such as Dim, Private, Public, or Static).
How to return INT from variant in C + +?
For example, if the VARIANT type is VT_INT, then get the int from the variant and can use something like: returnInt can be returned as an Out parameter from a C++ function in a C++ dll that can be called from C#. The C++ dll needs to use /clr option. Can use similar approach for other data types.