new IntPtr(0) vs. IntPtr.Zero

c# .net pinvoke
Yuval Peled picture Yuval Peled · Feb 18, 2009 · Viewed 22.8k times · Source

Is there any difference between the two statements:

IntPtr myPtr = new IntPtr(0);
IntPtr myPtr2 = IntPtr.Zero;

I have seen many samples that use PInvoke that prefer the first syntax if the myPtr argument is sent by ref to the called function. If I'll replace all new IntPtr(0) with IntPtr.Zero in my application, will it cause any damage?

Answer

Keith picture Keith · Feb 18, 2009

IntPtr is a value type, so unlike String.Empty there's relatively little benefit in having the static property IntPtr.Zero

As soon as you pass IntPtr.Zero anywhere you'll get a copy, so for variable initialisation it makes no difference:

IntPtr myPtr = new IntPtr(0);
IntPtr myPtr2 = IntPtr.Zero;

//using myPtr or myPtr2 makes no difference
//you can pass myPtr2 by ref, it's now a copy

There is one exception, and that's comparison:

if( myPtr != new IntPtr(0) ) {
    //new pointer initialised to check
}

if( myPtr != IntPtr.Zero ) {
    //no new pointer needed
}

As a couple of posters have already said.

Related questions

Bring a window to the front in WPF

How can I bring my WPF application to the front of the desktop? So far I've tried: SwitchToThisWindow(new WindowInteropHelper(Application.Current.MainWindow).Handle, true); SetWindowPos(new WindowInteropHelper(Application.Current.MainWindow).Handle, IntPtr.Zero, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE); SetForegroundWindow(new …

Read More
Win32 API function to programmatically enable/disable device

I am writing a small C# app to disable a device (my laptop touchpad) whenever another mouse device is detected, and enable the touchpad again if a mouse is not detected. I am not even able to disable the touchpad …

Read More
Using a 32bit or 64bit dll in C# DllImport

Here is the situation, I'm using a C based dll in my dot.net application. There are 2 dlls, one is 32bit called MyDll32.dll and the other is a 64bit version called MyDll64.dll. There is a static variable holding …

Read More