VBA IsObject Function

The VBA IsObject function is used to determine whether a given variable or expression is an object or not. An object in VBA can be a range, a chart, a workbook, a worksheet, or any other element that can be manipulated using VBA code. The IsObject function checks whether the given variable or expression is an object and returns a boolean value of True or False. It is useful when working with different types of data and allows users to handle objects and non-objects differently in their code.

VBA IsObject Function – Purpose, Syntax and Arguments

Purpose

The purpose of the IsObject function in VBA is to determine the type of data that is being dealt with, specifically identifying whether it is an object or not. This function is commonly used when working with various types of data in VBA to ensure that the correct methods and properties are being used for each type.

Syntax

IsObject(varName)

Arguments

• varName: This is a required argument that represents the variable or expression being checked for object type.

Example

Suppose we have a variable ‘myRange’ that represents a range object in our VBA code. We can use the IsObject function to check whether this variable is an object or not, as shown in the code below:

Sub CheckObject()
    Dim myRange As Range
    Set myRange = Range("A1:B5")
    
    If IsObject(myRange) Then
        MsgBox "myRange is an object."
    Else
        MsgBox "myRange is not an object."
    End If
End Sub

In this example, since ‘myRange’ is indeed an object (a range), the message box will display “myRange is an object.”

Remarks and Important Notes

• The IsObject function only works with variables or expressions, not values. Therefore, it will not work if the argument passed to it is a literal value or a function that returns a value.
• If the given argument is an object variable, it will return a value of True. However, if the variable is not an object, it will return False.
• The IsObject function can also be used with the ‘Not’ operator to check whether a variable is not an object. For example, ‘Not IsObject(myRange)’ will return True if the variable is not an object.
• When using the IsObject function, it is important to properly handle any non-object values that might be encountered, to avoid throwing errors in the code.

Understanding VBA IsObject Function with Examples

Example 1: Checking if an Object Exists

The IsObject function in VBA is commonly used to check whether a variable refers to an object or not. This can be useful when working with multiple objects and wanting to make sure that a particular object exists before performing any operations on it.
To use this function, you simply pass the variable name as an argument and it will return True or False depending on whether the variable refers to an object or not.

Dim obj as Object
Set obj = Worksheets("Sheet1")
 
If IsObject(obj) Then
    'Do something with the object
End If

1. The first line declares a variable obj of type Object.
2. The second line assigns a worksheet to the obj variable.
3. The If statement then uses the IsObject function to check if obj refers to an object.
4. If IsObject(obj) returns True, then the code between Then and End If will be executed.

Explanation

The IsObject function returns True if the argument passed to it is an object and False otherwise. In the example, the variable obj has been assigned a worksheet object and hence the IsObject function will return True. This allows us to safely perform operations on the obj variable (in this case, we can access the Worksheets(“Sheet1”) object). If the variable was not assigned an object, IsObject(obj) would return False and the code between Then and End If would not be executed, preventing any errors.

Example 2: Determining the Type of an Object

The IsObject function can also be used to determine the type of an object, which can be useful in certain situations. For example, if you have a variable that refers to an object, but you are not sure what type of object it is, you can use the IsObject function to determine its type.

Dim obj as Object
Set obj = Worksheets("Sheet1")
 
If IsObject(obj) Then
    If IsObject(obj) = Worksheet Then
        MsgBox "The object is a worksheet."
    End If
End If

1. The first line declares a variable obj of type Object.
2. The second line assigns a worksheet to the obj variable.
3. The first If statement uses the IsObject function to check if obj refers to an object.
4. If IsObject(obj) returns True, then the second If statement checks if the type of the object is Worksheet.
5. Finally, a message box is displayed informing the user that the object is a worksheet.

Explanation

In this example, the IsObject function is used twice. The first time, it is used to check if the obj variable refers to an object. If this is true, the second If statement is executed to check if the type of the object is Worksheet. If this is also true, then the message box is displayed. This shows that the IsObject function can be used to not only determine the existence of an object, but also its type.

Example 3: Using IsObject with Arrays

The IsObject function can also be used with arrays in VBA. This is because an array is also considered an object in VBA. Let’s take a look at an example:

Dim arr() As Variant
arr = Array(1, 2, 3)
 
If IsObject(arr) Then
    MsgBox "The array is an object."
End If

1. The first line declares a dynamic array named arr.
2. The second line assigns the array arr with three elements.
3. The If statement uses the IsObject function to check if arr is an object.
4. If IsObject(arr) returns True, then a message box is displayed informing the user that arr is an object.

Explanation

In this example, the IsObject function is used to check if arr is an object. Since arr is an array, it is also considered an object and hence the IsObject function will return True. This can be useful when working with arrays and wanting to make sure that the variable referring to the array is, in fact, an object.

In conclusion

The IsObject function in VBA is a useful function when working with objects and arrays. It can be used to check the existence of an object, determine the type of an object, and even work with arrays. Understanding how this function works and how it can be used can make your code more robust and prevent unexpected errors. So next time you’re working with objects in VBA, remember to use the IsObject function to ensure everything works smoothly.