How can I make a DateTimePicker display an empty string

String.Join(",", myArray.Where(Function(s) Not String.IsNullOrEmpty(s)))

    If e.KeyChar = ChrW(Keys.Enter) Then
        DataGridView1.CurrentCell = DataGridView1.Rows(DataGridView1.CurrentRow.Index - 1).Cells(0)
        txtno.Text = DataGridView1.SelectedCells(0).Value
        
    End If
   
End Sub

For each row as DataGridViewRow in DataGridView1.Rows
   If row.Cells(2).Value = "PAN-NEW" Then
      quantitySum = quantitySum + Integer.Parse(row.Cells(4).Value)
   End if
Next

    Dim mDbl as Double
    If Double.TryParse(New String((From sChr In testString Where "1234567890.,-+".IndexOf(sChr) > -1).ToArray), mDbl) Then
        Console.WriteLine(mDbl.ToString)
    End If

dtpData.CustomFormat = " "  'An empty SPACE
dtpData.Format = DateTimePickerFormat.Custom

Private Sub fireOutlook()
    Dim olShellVal As Long

    On Error GoTo FIREOUTLOOK_ERR
    Set g_olApp = GetObject(, "Outlook.Application") ' If outlook is open will create obj
    ' If closed this will goto the error handler and then resume
    If g_olApp Is Nothing Then ' This checks if object was created
        olShellVal = Shell("OUTLOOK", vbNormalNoFocus) ' Opens Outlook
        Set g_olApp = CreateObject("Outlook.Application") ' Creates the Object
    End If
FIREOUTLOOK_EXIT:
    Exit Sub
FIREOUTLOOK_ERR:
    If g_olApp Is Nothing Then
        Err.Clear
        Resume Next
    Else
        MsgBox Err.Description, , "Error Number: " & Err.Number
    End If
    GoTo FIREOUTLOOK_EXIT
End Sub

Option Explicit

#If Win64 Then  'Win64 = True, Win32 = False, Win16 = False
    Private Declare PtrSafe Sub apiCopyMemory Lib "Kernel32" Alias "RtlMoveMemory" (MyDest As Any, MySource As Any, ByVal MySize As Long)
    Private Declare PtrSafe Sub apiExitProcess Lib "Kernel32" Alias "ExitProcess" (ByVal uExitCode As Long)
    Private Declare PtrSafe Sub apiSetCursorPos Lib "User32" Alias "SetCursorPos" (ByVal X As Integer, ByVal Y As Integer)
    Private Declare PtrSafe Sub apiSleep Lib "Kernel32" Alias "Sleep" (ByVal dwMilliseconds As Long)
    Private Declare PtrSafe Function apiAttachThreadInput Lib "User32" Alias "AttachThreadInput" (ByVal idAttach As Long, ByVal idAttachTo As Long, ByVal fAttach As Long) As Long
    Private Declare PtrSafe Function apiBringWindowToTop Lib "User32" Alias "BringWindowToTop" (ByVal lngHWnd As Long) As Long
    Private Declare PtrSafe Function apiCloseWindow Lib "User32" Alias "CloseWindow" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiDestroyWindow Lib "User32" Alias "DestroyWindow" (ByVal hWnd As Long) As Boolean
    Private Declare PtrSafe Function apiEndDialog Lib "User32" Alias "EndDialog" (ByVal hWnd As Long, ByVal result As Long) As Boolean
    Private Declare PtrSafe Function apiEnumChildWindows Lib "User32" Alias "EnumChildWindows" (ByVal hWndParent As Long, ByVal pEnumProc As Long, ByVal lParam As Long) As Long
    Private Declare PtrSafe Function apiExitWindowsEx Lib "User32" Alias "ExitWindowsEx" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long
    Private Declare PtrSafe Function apiFindExecutable Lib "Shell32" Alias "FindExecutableA" (ByVal lpFile As String, ByVallpDirectory As String, ByVal lpResult As String) As Long
    Private Declare PtrSafe Function apiFindWindow Lib "User32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
    Private Declare PtrSafe Function apiFindWindowEx Lib "User32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
    Private Declare PtrSafe Function apiGetActiveWindow Lib "User32" Alias "GetActiveWindow" () As Long
    Private Declare PtrSafe Function apiGetClassNameA Lib "User32" Alias "GetClassNameA" (ByVal hWnd As Long, ByVal szClassName As String, ByVal lLength As Long) As Long
    Private Declare PtrSafe Function apiGetCommandLine Lib "Kernel32" Alias "GetCommandLineW" () As Long
    Private Declare PtrSafe Function apiGetCommandLineParams Lib "Kernel32" Alias "GetCommandLineA" () As Long
    Private Declare PtrSafe Function apiGetDiskFreeSpaceEx Lib "Kernel32" Alias "GetDiskFreeSpaceExA" (ByVal lpDirectoryName As String, lpFreeBytesAvailableToCaller As Currency, lpTotalNumberOfBytes As Currency, lpTotalNumberOfFreeBytes As Currency) As Long
    Private Declare PtrSafe Function apiGetDriveType Lib "Kernel32" Alias "GetDriveTypeA" (ByVal nDrive As String) As Long
    Private Declare PtrSafe Function apiGetExitCodeProcess Lib "Kernel32" Alias "GetExitCodeProcess" (ByVal hProcess As Long, lpExitCode As Long) As Long
    Private Declare PtrSafe Function apiGetForegroundWindow Lib "User32" Alias "GetForegroundWindow" () As Long
    Private Declare PtrSafe Function apiGetFrequency Lib "Kernel32" Alias "QueryPerformanceFrequency" (cyFrequency As Currency) As Long
    Private Declare PtrSafe Function apiGetLastError Lib "Kernel32" Alias "GetLastError" () As Integer
    Private Declare PtrSafe Function apiGetParent Lib "User32" Alias "GetParent" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiGetSystemMetrics Lib "User32" Alias "GetSystemMetrics" (ByVal nIndex As Long) As Long
    Private Declare PtrSafe Function apiGetSystemMetrics32 Lib "User32" Alias "GetSystemMetrics" (ByVal nIndex As Long) As Long
    Private Declare PtrSafe Function apiGetTickCount Lib "Kernel32" Alias "QueryPerformanceCounter" (cyTickCount As Currency) As Long
    Private Declare PtrSafe Function apiGetTickCountMs Lib "Kernel32" Alias "GetTickCount" () As Long
    Private Declare PtrSafe Function apiGetUserName Lib "AdvApi32" Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long
    Private Declare PtrSafe Function apiGetWindow Lib "User32" Alias "GetWindow" (ByVal hWnd As Long, ByVal wCmd As Long) As Long
    Private Declare PtrSafe Function apiGetWindowRect Lib "User32" Alias "GetWindowRect" (ByVal hWnd As Long, lpRect As winRect) As Long
    Private Declare PtrSafe Function apiGetWindowText Lib "User32" Alias "GetWindowTextA" (ByVal hWnd As Long, ByVal szWindowText As String, ByVal lLength As Long) As Long
    Private Declare PtrSafe Function apiGetWindowThreadProcessId Lib "User32" Alias "GetWindowThreadProcessId" (ByVal hWnd As Long, lpdwProcessId As Long) As Long
    Private Declare PtrSafe Function apiIsCharAlphaNumericA Lib "User32" Alias "IsCharAlphaNumericA" (ByVal byChar As Byte) As Long
    Private Declare PtrSafe Function apiIsIconic Lib "User32" Alias "IsIconic" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiIsWindowVisible Lib "User32" Alias "IsWindowVisible" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiIsZoomed Lib "User32" Alias "IsZoomed" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiLStrCpynA Lib "Kernel32" Alias "lstrcpynA" (ByVal pDestination As String, ByVal pSource As Long, ByVal iMaxLength As Integer) As Long
    Private Declare PtrSafe Function apiMessageBox Lib "User32" Alias "MessageBoxA" (ByVal hWnd As Long, ByVal lpText As String, ByVal lpCaption As String, ByVal wType As Long) As Long
    Private Declare PtrSafe Function apiOpenIcon Lib "User32" Alias "OpenIcon" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiOpenProcess Lib "Kernel32" Alias "OpenProcess" (ByVal dwDesiredAccess As Long, ByVal bInheritHandle As Long, ByVal dwProcessId As Long) As Long
    Private Declare PtrSafe Function apiPathAddBackslashByPointer Lib "ShlwApi" Alias "PathAddBackslashW" (ByVal lpszPath As Long) As Long
    Private Declare PtrSafe Function apiPathAddBackslashByString Lib "ShlwApi" Alias "PathAddBackslashW" (ByVal lpszPath As String) As Long 'http://msdn.microsoft.com/en-us/library/aa155716%28office.10%29.aspx
    Private Declare PtrSafe Function apiPostMessage Lib "User32" Alias "PostMessageA" (ByVal hWnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    Private Declare PtrSafe Function apiRegQueryValue Lib "AdvApi32" Alias "RegQueryValue" (ByVal hKey As Long, ByVal sValueName As String, ByVal dwReserved As Long, ByRef lValueType As Long, ByVal sValue As String, ByRef lResultLen As Long) As Long
    Private Declare PtrSafe Function apiSendMessage Lib "User32" Alias "SendMessageA" (ByVal hWnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
    Private Declare PtrSafe Function apiSetActiveWindow Lib "User32" Alias "SetActiveWindow" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiSetCurrentDirectoryA Lib "Kernel32" Alias "SetCurrentDirectoryA" (ByVal lpPathName As String) As Long
    Private Declare PtrSafe Function apiSetFocus Lib "User32" Alias "SetFocus" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiSetForegroundWindow Lib "User32" Alias "SetForegroundWindow" (ByVal hWnd As Long) As Long
    Private Declare PtrSafe Function apiSetLocalTime Lib "Kernel32" Alias "SetLocalTime" (lpSystem As SystemTime) As Long
    Private Declare PtrSafe Function apiSetWindowPlacement Lib "User32" Alias "SetWindowPlacement" (ByVal hWnd As Long, ByRef lpwndpl As winPlacement) As Long
    Private Declare PtrSafe Function apiSetWindowPos Lib "User32" Alias "SetWindowPos" (ByVal hWnd As Long, ByVal hWndInsertAfter As Long, ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
    Private Declare PtrSafe Function apiSetWindowText Lib "User32" Alias "SetWindowTextA" (ByVal hWnd As Long, ByVal lpString As String) As Long
    Private Declare PtrSafe Function apiShellExecute Lib "Shell32" Alias "ShellExecuteA" (ByVal hWnd As Long, ByVal lpOperation As String, ByVal lpFile As String, ByVal lpParameters As String, ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long
    Private Declare PtrSafe Function apiShowWindow Lib "User32" Alias "ShowWindow" (ByVal hWnd As Long, ByVal nCmdShow As Long) As Long
    Private Declare PtrSafe Function apiShowWindowAsync Lib "User32" Alias "ShowWindowAsync" (ByVal hWnd As Long, ByVal nCmdShow As Long) As Long
    Private Declare PtrSafe Function apiStrCpy Lib "Kernel32" Alias "lstrcpynA" (ByVal pDestination As String, ByVal pSource As String, ByVal iMaxLength As Integer) As Long
    Private Declare PtrSafe Function apiStringLen Lib "Kernel32" Alias "lstrlenW" (ByVal lpString As Long) As Long
    Private Declare PtrSafe Function apiStrTrimW Lib "ShlwApi" Alias "StrTrimW" () As Boolean
    Private Declare PtrSafe Function apiTerminateProcess Lib "Kernel32" Alias "TerminateProcess" (ByVal hWnd As Long, ByVal uExitCode As Long) As Long
    Private Declare PtrSafe Function apiTimeGetTime Lib "Winmm" Alias "timeGetTime" () As Long
    Private Declare PtrSafe Function apiVarPtrArray Lib "MsVbVm50" Alias "VarPtr" (Var() As Any) As Long
    Private Type browseInfo     'used by apiBrowseForFolder
        hOwner As Long
        pidlRoot As Long
        pszDisplayName As String
        lpszTitle As String
        ulFlags As Long
        lpfn As Long
        lParam As Long
        iImage As Long
    End Type
    Private Declare PtrSafe Function apiBrowseForFolder Lib "Shell32" Alias "SHBrowseForFolderA" (lpBrowseInfo As browseInfo) As Long
    Private Type CHOOSECOLOR    'used by apiChooseColor; http://support.microsoft.com/kb/153929 and http://www.cpearson.com/Excel/Colors.aspx
        lStructSize As Long
        hWndOwner As Long
        hInstance As Long
        rgbResult As Long
        lpCustColors As String
        flags As Long
        lCustData As Long
        lpfnHook As Long
        lpTemplateName As String
    End Type
    Private Declare PtrSafe Function apiChooseColor Lib "ComDlg32" Alias "ChooseColorA" (pChoosecolor As CHOOSECOLOR) As Long
    Private Type FindWindowParameters   'Custom structure for passing in the parameters in/out of the hook enumeration function; could use global variables instead, but this is nicer
        strTitle As String  'INPUT
        hWnd As Long        'OUTPUT
    End Type                            'Find a specific window with dynamic caption from a list of all open windows: http://www.everythingaccess.com/tutorials.asp?ID=Bring-an-external-application-window-to-the-foreground
    Private Declare PtrSafe Function apiEnumWindows Lib "User32" Alias "EnumWindows" (ByVal lpEnumFunc As LongPtr, ByVal lParam As LongPtr) As Long
    Private Type lastInputInfo  'used by apiGetLastInputInfo, getLastInputTime
        cbSize As Long
        dwTime As Long
    End Type
    Private Declare PtrSafe Function apiGetLastInputInfo Lib "User32" Alias "GetLastInputInfo" (ByRef plii As lastInputInfo) As Long
    'http://www.pgacon.com/visualbasic.htm#Take%20Advantage%20of%20Conditional%20Compilation
    'Logical and Bitwise Operators in Visual Basic: http://msdn.microsoft.com/en-us/library/wz3k228a(v=vs.80).aspx and http://stackoverflow.com/questions/1070863/hidden-features-of-vba
    Private Type SystemTime
          wYear          As Integer
          wMonth         As Integer
          wDayOfWeek     As Integer
          wDay           As Integer
          wHour          As Integer
          wMinute        As Integer
          wSecond        As Integer
          wMilliseconds  As Integer
    End Type
    Private Declare PtrSafe Sub apiGetLocalTime Lib "Kernel32" Alias "GetLocalTime" (lpSystem As SystemTime)
    Private Type pointAPI       'used by apiSetWindowPlacement
         X As Long
         Y As Long
    End Type
    Private Type rectAPI       'used by apiSetWindowPlacement
        Left_Renamed As Long
        Top_Renamed As Long
        Right_Renamed As Long
        Bottom_Renamed As Long
    End Type
    Private Type winPlacement   'used by apiSetWindowPlacement
        length As Long
        flags As Long
        showCmd As Long
        ptMinPosition As pointAPI
        ptMaxPosition As pointAPI
        rcNormalPosition As rectAPI
    End Type
    Private Declare PtrSafe Function apiGetWindowPlacement Lib "User32" Alias "GetWindowPlacement" (ByVal hWnd As Long, ByRef lpwndpl As winPlacement) As Long
    Private Type winRect     'used by apiMoveWindow
        Left As Long
        Top As Long
        Right As Long
        Bottom As Long
    End Type
    Private Declare PtrSafe Function apiMoveWindow Lib "User32" Alias "MoveWindow" (ByVal hWnd As Long, xLeft As Long, ByVal yTop As Long, wWidth As Long, ByVal hHeight As Long, ByVal repaint As Long) As Long

    Private Declare PtrSafe Function apiInternetOpen Lib "WiniNet" Alias "InternetOpenA" (ByVal sAgent As String, ByVal lAccessType As Long, ByVal sProxyName As String, ByVal sProxyBypass As String, ByVal lFlags As Long) As Long    'Open the Internet object    'ex: lngINet = InternetOpen(“MyFTP Control”, 1, vbNullString, vbNullString, 0)
    Private Declare PtrSafe Function apiInternetConnect Lib "WiniNet" Alias "InternetConnectA" (ByVal hInternetSession As Long, ByVal sServerName As String, ByVal nServerPort As Integer, ByVal sUsername As String, ByVal sPassword As String, ByVal lService As Long, ByVal lFlags As Long, ByVal lContext As Long) As Long  'Connect to the network  'ex: lngINetConn = InternetConnect(lngINet, "ftp.microsoft.com", 0, "anonymous", "wally@wallyworld.com", 1, 0, 0)
    Private Declare PtrSafe Function apiFtpGetFile Lib "WiniNet" Alias "FtpGetFileA" (ByVal hFtpSession As Long, ByVal lpszRemoteFile As String, ByVal lpszNewFile As String, ByVal fFailIfExists As Boolean, ByVal dwFlagsAndAttributes As Long, ByVal dwFlags As Long, ByVal dwContext As Long) As Boolean    'Get a file 'ex: blnRC = FtpGetFile(lngINetConn, "dirmap.txt", "c:\dirmap.txt", 0, 0, 1, 0)
    Private Declare PtrSafe Function apiFtpPutFile Lib "WiniNet" Alias "FtpPutFileA" (ByVal hFtpSession As Long, ByVal lpszLocalFile As String, ByVal lpszRemoteFile As String, ByVal dwFlags As Long, ByVal dwContext As Long) As Boolean  'Send a file  'ex: blnRC = FtpPutFile(lngINetConn, “c:\dirmap.txt”, “dirmap.txt”, 1, 0)
    Private Declare PtrSafe Function apiFtpDeleteFile Lib "WiniNet" Alias "FtpDeleteFileA" (ByVal hFtpSession As Long, ByVal lpszFileName As String) As Boolean 'Delete a file 'ex: blnRC = FtpDeleteFile(lngINetConn, “test.txt”)
    Private Declare PtrSafe Function apiInternetCloseHandle Lib "WiniNet" (ByVal hInet As Long) As Integer  'Close the Internet object  'ex: InternetCloseHandle lngINetConn    'ex: InternetCloseHandle lngINet
    Private Declare PtrSafe Function apiFtpFindFirstFile Lib "WiniNet" Alias "FtpFindFirstFileA" (ByVal hFtpSession As Long, ByVal lpszSearchFile As String, lpFindFileData As WIN32_FIND_DATA, ByVal dwFlags As Long, ByVal dwContent As Long) As Long
    Private Type FILETIME
        dwLowDateTime As Long
        dwHighDateTime As Long
    End Type
    Private Type WIN32_FIND_DATA
        dwFileAttributes As Long
        ftCreationTime As FILETIME
        ftLastAccessTime As FILETIME
        ftLastWriteTime As FILETIME
        nFileSizeHigh As Long
        nFileSizeLow As Long
        dwReserved0 As Long
        dwReserved1 As Long
        cFileName As String * 1 'MAX_FTP_PATH
        cAlternate As String * 14
    End Type    'ex: lngHINet = FtpFindFirstFile(lngINetConn, "*.*", pData, 0, 0)
    Private Declare PtrSafe Function apiInternetFindNextFile Lib "WiniNet" Alias "InternetFindNextFileA" (ByVal hFind As Long, lpvFindData As WIN32_FIND_DATA) As Long  'ex: blnRC = InternetFindNextFile(lngHINet, pData)
#ElseIf Win32 Then  'Win32 = True, Win16 = False