How can I make a DateTimePicker display an empty string?

In case anybody has an issue with setting datetimepicker control to blank during the form load event, and then show the current date as needed, here is an example:

MAKE SURE THAT CustomFormat = " " has same number of spaces (at least one space) in both methods

Private Sub setDateTimePickerBlank(ByVal dateTimePicker As DateTimePicker)    

    dateTimePicker.Visible = True
    dateTimePicker.Format = DateTimePickerFormat.Custom
    dateTimePicker.CustomFormat = "    " 
End Sub


Private Sub dateTimePicker_MouseHover(ByVal sender As Object, ByVal e As 
                    System.EventArgs) Handles dateTimePicker.MouseHover

    Dim dateTimePicker As DateTimePicker = CType(sender, DateTimePicker)
    If dateTimePicker.Text = "    " Then
        dateTimePicker.Text = Format(DateTime.Now, "MM/dd/yyyy")
    End If
End Sub

Obfuscating the value by using the CustomFormat property, using checkbox cbEnableEndDate as the flag to indicate whether other code should ignore the value:

If dateTaskEnd > Date.FromOADate(0) Then
    dtTaskEnd.Format = DateTimePickerFormat.Custom
    dtTaskEnd.CustomFormat = "yyyy-MM-dd"
    dtTaskEnd.Value = dateTaskEnd 
    dtTaskEnd.Enabled = True
    cbEnableEndDate.Checked = True
Else
    dtTaskEnd.Format = DateTimePickerFormat.Custom
    dtTaskEnd.CustomFormat = " "
    dtTaskEnd.Value = Date.FromOADate(0)
    dtTaskEnd.Enabled = False
    cbEnableEndDate.Checked = False
End If

Just set the property as follows:

When the user press "clear button" or "delete key" do

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

On DateTimePicker1_ValueChanged event do

dtpData.CustomFormat = "dd/MM/yyyy hh:mm:ss"

this worked for me for c#

if (enableEndDateCheckBox.Checked == true)
{
    endDateDateTimePicker.Enabled = true;
    endDateDateTimePicker.Format = DateTimePickerFormat.Short;                
}
else
{
    endDateDateTimePicker.Enabled = false;
    endDateDateTimePicker.Format = DateTimePickerFormat.Custom;
    endDateDateTimePicker.CustomFormat = " ";
}

nice one guys!