How to: Validate Strings That Represent Dates or Times (Visual Basic)


Updated: July 20, 2015

For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.

The following code example sets a Boolean value that indicates whether a string represents a valid date or time.

        Dim isValidDate As Boolean = IsDate("01/01/03")
        Dim isValidTime As Boolean = IsDate("9:30 PM")

Replace ("01/01/03") and "9:30 PM" with the date and time you want to validate. You can replace the string with another hard-coded string, with a String variable, or with a method that returns a string, such as InputBox.

Use this method to validate the string before trying to convert the String to a DateTime variable. By checking the date or time first, you can avoid generating an exception at run time.

Validating Strings in Visual Basic