// Allocates a new string on the unmanaged heap, and stores the pointer
// so we can free it later
private IntPtr MakeNewString(string s, NativeMethods.TASKDIALOG_ELEMENTS element)
{
IntPtr newStringPtr = Marshal.StringToHGlobalUni(s);
updatedStrings[(int)element] = newStringPtr;
return(newStringPtr);
}
// Checks to see if the given element already has an updated string, and if so,
// frees it. This is done in preparation for a call to MakeNewString(), to prevent
// leaks from multiple updates calls on the same element within a single native dialog lifetime.
private void FreeOldString(NativeMethods.TASKDIALOG_ELEMENTS element)
{
int elementIndex = (int)element;
if (updatedStrings[elementIndex] != IntPtr.Zero)
{
Marshal.FreeHGlobal(updatedStrings[elementIndex]);
updatedStrings[elementIndex] = IntPtr.Zero;
}
}
private void UpdateTextCore(string s, NativeMethods.TASKDIALOG_ELEMENTS element)
{
AssertCurrentlyShowing();
FreeOldString(element);
SendMessageHelper(
NativeMethods.TASKDIALOG_MESSAGES.TDM_SET_ELEMENT_TEXT,
(int)element,
(long)MakeNewString(s, element));
}
