Could any one help me with this error warning I am getting with my function.
Code:
 Private Function GetShiftType() As String
        Dim StartTime, EndTime As Date
        Dim StartHour, EndHour As Double
        StartTime = dtpStartTime.Text
        EndTime = dtpEndTime.Text

        StartHour = StartTime.TimeOfDay.TotalHours
        EndHour = EndTime.TimeOfDay.TotalHours

        If StartHour >= 7.0 AndAlso StartHour <= 8.5 AndAlso EndHour >= 12.0 AndAlso EndHour <= 16.0 Then
            txtShiftType.Text = "Ealy"
            btnUpdate.Focus()
        ElseIf StartHour >= 12.0 AndAlso StartHour <= 15.0 AndAlso EndHour >= 19.0 AndAlso EndHour <= 21.0 Then
            txtShiftType.Text = "Late"
            btnUpdate.Focus()
        ElseIf StartHour >= 7.0 AndAlso StartHour <= 8.5 AndAlso EndHour >= 19.0 AndAlso EndHour <= 21.0 Then
            txtShiftType.Text = "Long Day"
            btnUpdate.Focus()
        ElseIf StartHour >= 19.0 AndAlso StartHour <= 21.0 AndAlso EndHour >= 7.0 AndAlso EndHour <= 9.0 Then
            txtShiftType.Text = "Night"
            btnUpdate.Focus()
        ElseIf StartHour >= 15.0 AndAlso StartHour <= 18.0 AndAlso EndHour >= 0.0 Then
            txtShiftType.Text = "Toalight"
            btnUpdate.Focus()
        Else
            MessageBox.Show("The specified start and end times do not match any known shift.", "Check shift time")
            dtpStartTime.Focus()
        End If

    End Function
Then end function is underline and the error message is as follows (Function 'GetShiftType' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.)
Thanks