private bool Validate(DevMode devMode)
{
bool settingsChanged = false;
// Create a copy of the devmode before validating... if anything
// changes, then we'll report it
DevMode originalDevMode = devMode.Clone();
// Validate the DEVMODE via a call to the driver.
SetDocumentProperties(devMode.ByteData, true);
// Compare the devmods to decide whether any features
// changed. Ignore changes in the DM_FORMNAME field
// because the shim may clear it in selecting a paper size.
// If other paper size fields are set in the DEVMODE, ignore the form field
// because some driver change set / clear the form field during DocumentProperties
// without actually changing the selected paper size.
if (originalDevMode.IsAnyFieldSet(DevModeFields.DM_PAPERWIDTH | DevModeFields.DM_PAPERLENGTH | DevModeFields.DM_PAPERSIZE))
{
originalDevMode.Fields &= ~DevModeFields.DM_FORMNAME;
originalDevMode.Fields |= devMode.Fields & DevModeFields.DM_FORMNAME;
originalDevMode.FormName = devMode.FormName;
}
// Ignore device name in the original DEVMODE. Copy the full buffer so that any extra
// garbage in the device name after the string also matches. The device name isn't actually
// a setting per-se. Version changes should be noted, because the same content may mean different
// things in different versions of a driver.
originalDevMode.DeviceName = devMode.DeviceName;
// Do the actual comparison. Note that if there are issues in the private DEVMODE similar
// to the issues fixed up in the public DEVMODE, there may be false positive return values
// from this API. There's no way to fix this issue.
for (int i = 0; i < originalDevMode.ByteData.Length; i++)
{
if (originalDevMode.ByteData[i] != devMode.ByteData[i])
{
settingsChanged = true;
}
}
WinSpoolPrinterCapabilities capabilities = GetCapabilities(null);
try
{
PrintSchemaShim.PruneFeatures(devMode, capabilities);
}
finally
{
capabilities.Release();
}
return(settingsChanged);
}
