How do you get total amount of RAM the computer has?

Question

Using C#, I want to get the total amount of RAM that my computer has. With the PerformanceCounter I can get the amount of Available ram, by setting:

counter.CategoryName = "Memory"; counter.Countername = "Available MBytes"; 

But I can't seem to find a way to get the total amount of memory. How would I go about doing this?

Update:

MagicKat: I saw that when I was searching, but it doesn't work - "Are you missing an assembly or reference?". I've looked to add that to the References, but I don't see it there.

Answer 1

Add a reference to Microsoft.VisualBasic and a using Microsoft.VisualBasic.Devices;.

The ComputerInfo class has all the information that you need.

Answer 2

The Windows API function GlobalMemoryStatusEx can be called with p/invoke:

  [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]   private class MEMORYSTATUSEX   {      public uint dwLength;      public uint dwMemoryLoad;      public ulong ullTotalPhys;      public ulong ullAvailPhys;      public ulong ullTotalPageFile;      public ulong ullAvailPageFile;      public ulong ullTotalVirtual;      public ulong ullAvailVirtual;      public ulong ullAvailExtendedVirtual;      public MEMORYSTATUSEX()      {         this.dwLength = (uint)Marshal.SizeOf(typeof(NativeMethods.MEMORYSTATUSEX));      }   }     [return: MarshalAs(UnmanagedType.Bool)]   [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]   static extern bool GlobalMemoryStatusEx([In, Out] MEMORYSTATUSEX lpBuffer); 

Then use like:

ulong installedMemory; MEMORYSTATUSEX memStatus = new MEMORYSTATUSEX(); if( GlobalMemoryStatusEx( memStatus)) {     installedMemory = memStatus.ullTotalPhys; } 

Or you can use WMI (managed but slower) to query TotalPhysicalMemory in the Win32_ComputerSystem class.