VBA CVar Function

The VBA CVar function is used to convert a given value into a Variant data type in Visual Basic for Applications (VBA). This function is very similar to the ‘VarType’ function, except that it explicitly converts the value into a Variant data type, while the ‘VarType’ function only returns the data type of the given value. The CVar function is mainly used to handle different data types in VBA, where a value can be of any type and may need to be converted into a specific data type for further processing.

VBA CVar Function – Purpose, Syntax and Arguments

Purpose:

The main purpose of the CVar function is to convert a given value into a Variant data type in VBA. The Variant data type is a generic data type that can hold and handle values of any other data type. This is particularly useful in situations where the type of data is not known beforehand, or when the same variable needs to hold different types of data at different points in the code.

Syntax:

CVar(expression)

Arguments:

• expression: This is the value that needs to be converted into a Variant data type. It can be any valid VBA expression, such as a variable, a literal value, or a function that returns a value.

Example:

Let’s say we have a variable ‘x’ that contains an integer value, but we want to use it in a calculation that requires a number in the decimal format. In such a case, we can use the CVar function to convert the value of ‘x’ into a Variant data type, as shown in the code below:

Dim x as Integer
x = 5
Dim y as Variant
y = CVar(x)
MsgBox y

The ‘MsgBox’ function will display the value of ‘y’ as 5.0, which is equal to the value of ‘x’ but in the decimal format.

Remarks:

• The CVar function is useful when working with values of different data types in VBA, as it allows for easier handling and manipulation of these values.
• The CVar function will return a Variant data type, even if the given value is already a Variant. However, it will not convert the value further if it is already a Variant of a specific data type, such as an integer or string.
• The CVar function is particularly helpful when working with values that come from external sources, such as user input, text files, or databases, as it allows for their conversion into a more usable data type for further processing.

Important Notes:

• The CVar function will return an error if the given value is a Null value. In such cases, the ‘Nz’ function can be used to handle Null values before passing them to the CVar function.
• The CVar function is not used in VBA for Excel, as Excel has its own built-in data conversion functions. The CVar function is mainly used in other VBA-enabled applications, such as Microsoft Access, Word, and Outlook.

Understanding VBA CVar Function with Examples

Using CVar on Numeric Values

Description:
The CVar function is used to convert a value into its corresponding Variant data type in Visual Basic for Applications (VBA). It takes in a value and returns the value as a Variant data type. This function is used in scenarios where you want to store a value into a Variant variable, but the value’s data type is unknown. In this example, we will see how the CVar function is used on numeric values.

Dim num as Integer
num = 5
Dim varnum as Variant
varnum = CVar(num)
MsgBox varnum

1. First, we declare a variable called num of data type Integer and assign the value 5 to it.
2. In the next line, we declare a variable called varnum of data type Variant.
3. We then use the CVar function to convert the value of num into a Variant data type and store it in the varnum variable.
4. Finally, we use the MsgBox function to display the value of varnum in a message box. Since the CVar function has converted the value into a Variant data type, the message box will display the value 5 instead of “5”.

Explanation:
In this example, the CVar function is used to convert a numeric value into a Variant data type. This is useful when you want to store a value that could be of different data types, without explicitly declaring the data type of the variable. By using the CVar function, we can ensure that the value is properly converted and stored in the Variant data type variable.

Using CVar on String Values

Description:
The CVar function can also be used on string values to convert them into a Variant data type. In this example, we will see how the CVar function is used on string values.

Dim str as String
str = "Hello"
Dim varstr as Variant
varstr = CVar(str)
MsgBox varstr

1. First, we declare a variable called str of data type String and assign the value “Hello” to it.
2. In the next line, we declare a variable called varstr of data type Variant.
3. We then use the CVar function to convert the value of str into a Variant data type and store it in the varstr variable.
4. Finally, we use the MsgBox function to display the value of varstr in a message box. Since the CVar function has converted the value into a Variant data type, the message box will display the value “Hello”.

Explanation:
In this example, the CVar function is used to convert a string value into a Variant data type. This is useful when you want to store a value that could be of different data types, without explicitly declaring the data type of the variable. By using the CVar function, we can ensure that the value is properly converted and stored in the Variant data type variable.

Using CVar on Boolean Values

Description:
The CVar function can also be used on boolean values to convert them into a Variant data type. In this example, we will see how the CVar function is used on boolean values.

Dim boolval as Boolean
boolval = False
Dim varbool as Variant
varbool = CVar(boolval)
MsgBox varbool

1. First, we declare a variable called boolval of data type Boolean and assign the value False to it.
2. In the next line, we declare a variable called varbool of data type Variant.
3. We then use the CVar function to convert the value of boolval into a Variant data type and store it in the varbool variable.
4. Finally, we use the MsgBox function to display the value of varbool in a message box. Since the CVar function has converted the value into a Variant data type, the message box will display the value False.

Explanation:
In this example, the CVar function is used to convert a boolean value into a Variant data type. This is useful when you want to store a value that could be of different data types, without explicitly declaring the data type of the variable. By using the CVar function, we can ensure that the value is properly converted and stored in the Variant data type variable.

Using CVar on Arrays

Description:
The CVar function can also be used on arrays to convert them into a Variant data type. In this example, we will see how the CVar function is used on arrays.

Dim arr as Variant
arr = Array(1, 2, 3)
Dim vararr as Variant
vararr = CVar(arr)
MsgBox vararr(0)
MsgBox vararr(1)
MsgBox vararr(2)

1. First, we declare a variable called arr of data type Variant and assign the value of an array containing 1, 2, 3 to it.
2. In the next line, we declare a variable called vararr of data type Variant.
3. We then use the CVar function to convert the value of arr into a Variant data type and store it in the vararr variable.
4. Finally, we use the MsgBox function to display the values of vararr at index 0, 1, and 2 in separate message boxes. Since the CVar function has converted the array into a Variant data type, the message boxes will display the values 1, 2, and 3 respectively.

Explanation:
In this example, the CVar function is used to convert an array into a Variant data type. By using the CVar function, we can easily store the array in a Variant variable and access its elements without having to explicitly declare the variable as an array. This is useful when working with arrays of unknown size or data type.