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Try something like this to check the format of the time...<br />
Imports System.Text.RegularExpress<wbr />ions<br />
<br />
&nbsp; Function IsValidTime(ByVal strIn As String) As Boolean<br />
&nbsp; &nbsp; &nbsp; &nbsp; ' Return true if strIn is in valid SSN format.<br />
&nbsp; &nbsp; &nbsp; &nbsp; Return Regex.IsMatch(strIn, &quot;^\d{2}:\d{2}:\d{2}$&quot;)<br />
&nbsp; &nbsp; End Function
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Try something like this to check the format of the time...
Imports System.Text.RegularExpressions

  Function IsValidTime(ByVal strIn As String) As Boolean
        ' Return true if strIn is in valid SSN format.
        Return Regex.IsMatch(strIn, "^\d{2}:\d{2}:\d{2}$")
    End Function

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Thanks! &nbsp;TryParse was exactly what I was looking for.
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Thanks!  TryParse was exactly what I was looking for.

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I have a windows form with a textbox tbLength that displays a length of time for a scheduling program. &nbsp;The user can enter a start date/time from a time picker field, and can enter a length - the combo of these 2 calculates the end date/time. &nbsp;I need Length to be in a proper timespan format 1.00:00:00, etc. &nbsp;How can I validate the entered value is OK? &nbsp;Can I force the entered format to be 99.99:99:99?
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I have a windows form with a textbox tbLength that displays a length of time for a scheduling program.  The user can enter a start date/time from a time picker field, and can enter a length - the combo of these 2 calculates the end date/time.  I need Length to be in a proper timespan format 1.00:00:00, etc.  How can I validate the entered value is OK?  Can I force the entered format to be 99.99:99:99?

How do I validate that a correct format was entered?

Visual Basic .NET (VB.NET) is an object-oriented programming language implemented on the .NET framework, but also supported on other platforms such as Mono and Silverlight. Microsoft launched VB.NET as the successor to the Visual Basic language. Though it is similar in syntax to  Visual Basic pre-2002, it is not the same technology,

Visual Basic.NET

Visual Basic is Microsoft’s event-driven programming language and integrated development environment (IDE) for its Component Object Model (COM) programming model. It is relatively easy to learn and use because of its graphical development features and BASIC heritage. It has been replaced with VB.NET, and is very similar to VBA (Visual Basic for Applications), the programming language for the Microsoft Office product line.