The IsDate function in VBA (Visual Basic for Applications) is used to determine if an expression can be converted to a date. It returns True if the expression is a valid date or can be converted to a valid date; otherwise, it returns False.
Here’s how to use the IsDate function in VBA:
Basic Usage
VBA
In this example, the CheckIfDate subroutine checks different expressions using the IsDate function. The results of these checks are printed to the Immediate Window in the VBA Editor.
Remember that the IsDate function is locale-dependent, so the format of the date string it recognizes as valid can vary depending on your system’s regional settings. For example, “12/31/2023” may be recognized as a valid date in the United States, where the “mm/dd/yyyy” format is common, but not necessarily in countries where “dd/mm/yyyy” is the standard format.
Sub CheckIfDate()
Dim myValue As Variant
' Assign different types of values to the variable
myValue = "12/31/2023" ' This is a valid date string
Debug.Print myValue & " is a date: " & IsDate(myValue)
myValue = "Not a date" ' This is clearly not a date
Debug.Print myValue & " is a date: " & IsDate(myValue)
myValue = DateSerial(2023, 1, 31) ' This is a date object
Debug.Print myValue & " is a date: " & IsDate(myValue)
' Using with an invalid date string
myValue = "2023/31/12" ' This format is not recognized as a valid date
Debug.Print myValue & " is a date: " & IsDate(myValue)
End Sub