internal void NativeShow()
{
// Applies config struct and other settings, then
// calls main Win32 function.
if (settings == null)
{
throw new InvalidOperationException(
"An error has occurred in dialog configuration.");
}
// Do a last-minute parse of the various dialog control lists,
// and only allocate the memory at the last minute.
MarshalDialogControlStructs();
// Make the call and show the dialog.
// NOTE: this call is BLOCKING, though the thread
// WILL re-enter via the DialogProc.
try
{
showState = NativeDialogShowState.Showing;
// Here is the way we would use "vanilla" PInvoke to call TaskDialogIndirect;
// but if we did so here, we'd be at the mercy of the CLR's native DLL cache -
// see below for more details.
// HRESULT hresult = NativeMethods.TaskDialogIndirect(
// nativeDialogConfig,
// out selectedButtonID,
// out selectedRadioButtonID,
// out checkBoxChecked);
// Instead, we load comctl and bind to TaskDialogIndirect
// We do it this way so we can rigidly control
// which version of comctl32 is loaded,
// The CLR's PInvoke mechanism maintains a DLL cache that is
// NOT invalidated when the OS activation context is changed
// such that different DLL versions are needed.
IntPtr tdi = DllVersionManager.GetNativeFunctionPointer(
ExternDll.ComCtl32, "TaskDialogIndirect");
NativeMethods.TDIDelegate taskDialogFunctionPointer =
(NativeMethods.TDIDelegate)
Marshal.GetDelegateForFunctionPointer(
tdi,
typeof(NativeMethods.TDIDelegate)
);
// Invoke TaskDialogIndirect.
HRESULT hresult = taskDialogFunctionPointer(
nativeDialogConfig,
out selectedButtonID,
out selectedRadioButtonID,
out checkBoxChecked);
if (ErrorHelper.Failed(hresult))
{
string msg;
switch (hresult)
{
case HRESULT.E_INVALIDARG:
msg = "Invalid arguments to Win32 call.";
break;
case HRESULT.E_OUTOFMEMORY:
msg = "Dialog contents too complex.";
break;
default:
msg = String.Format(
"An unexpected internal error occurred in the Win32 call:{0:x}",
hresult);
break;
}
Exception e = Marshal.GetExceptionForHR((int)hresult);
throw new Win32Exception(msg, e);
}
}
finally
{
showState = NativeDialogShowState.Closed;
}
}