An ordinary VB developer shares his own successes and failures
PageSetupDialog Margins Conversion Fix
A definitive cure for the PageSetupDialog margins conversion bug.
Recently, I've been adding printing capabilities to one of the WinForms applications I wrote some time ago. One of the standard printing-related features I was going to implement was the page setup dialog. It seemed to be a piece of cake with the help of the built-inSystem.Windows.Forms.PageSetupDialog component. Just
assign it an instance of your PrintDocument-derived class and
invoke the ShowDialog method:
Imports System.Drawing.Printing Dim Doc As PrintDocument = New DataPrintDocument(...) Dim Dlg As New PageSetupDialog Dlg.Document = Doc If Dlg.ShowDialog() = DialogResult.OK Then ' Save the page settings for later use when printing / previewing... End IfIt turns out that when you live in a region where a 'metric' measurement system is being used, the
PageSetupDialog class
exposes a known conversion bug (see
the MS KB article).
I've Googled a bit (searched for "PageSetupDialog metric" on Google Groups) and I was able to find a solution to the problem - just convert the page margins to millimeters before displaying the dialog:
If System.Globalization.RegionInfo.CurrentRegion.IsMetric Then
dlg.Document.DefaultPageSettings.Margins = _
PrinterUnitConvert.Convert(dlg.Document.DefaultPageSettings.Margins, _
PrinterUnit.Display, PrinterUnit.TenthsOfAMillimeter)
End If
However, there are two problems with this approach:
First, the workaround should have been better encapsulated, because when MS releases a fix to the problem, we'll have to "fix our fix" once again. If we'd like to avoid recompilation, the fix must be controlled externally, preferably by a setting in the application's configuration file.
Second, the
System.Globalization.RegionInfo.CurrentRegion.IsMetric property returns
the metric setting for the whole region; it ignores what the user
might have specified in the Regional Options control panel applet
for the 'Measurement system' setting. That is, you can have US
measurement system active even if you have metric region
selected, and vice versa.
In order to solve the problems, I've encapsulated the fix in a simple
PageSetupDialogHelper class. Its usage is very simple -
just add the PageSetupDialogHelper.vb file to your project and then,
instead of calling the PageSetupDialog.ShowDialog instance
method, call the PageSetupDialogHelper.ShowDialog shared method
passing it the PageSetupDialog instance as an argument:
Dim Doc As PrintDocument = New DataPrintDocument(...) Dim Dlg As New PageSetupDialog Dlg.Document = Doc If PageSetupDialogHelper.ShowDialog(Dlg) = DialogResult.OK Then ' Save the page settings for later use when printing / previewing... End IfThe
PageSetupDialogHelper class correctly handles the
'Measurement system' setting (by using P/Invoke, not directly
reading the Control Panel's international registry keys as one of
the other solutions implemented). If Microsoft fixes the bug
sometime in the future, you can bypass the
PageSetupDialogHelper's workaround by adding the following key to
your application config file (under the <appSettings> section):
<add key="ApplyPageSetupDialogFix" value="no" />Here is a VB.NET demo project containing the
PageSetupDialogHelper class.
Enjoy!
(c) Palo Mraz, Friday, April 23, 2004