C# Signature:

[DllImport("kernel32.dll")]
static extern void GetSystemInfo(out SYSTEM_INFO lpSystemInfo);

User-Defined Types:

None.

Notes:

This API mapping demonstrates mapping a union in C#.

Tips & Tricks:

Please add some!

Sample Code:

using System;

using System.Runtime.InteropServices;

namespace TestGetSystemInfo

{

    public class WinApi
    {
    [DllImport("kernel32.dll")]
    public static extern void GetSystemInfo([MarshalAs(UnmanagedType.Struct)] ref SYSTEM_INFO lpSystemInfo);

    [StructLayout(LayoutKind.Sequential)]
    public struct SYSTEM_INFO
    {
        internal _PROCESSOR_INFO_UNION uProcessorInfo;
        public uint dwPageSize;
        public uint lpMinimumApplicationAddress;
        public uint lpMaximumApplicationAddress;
        public uint dwActiveProcessorMask;
        public uint dwNumberOfProcessors;
        public uint dwProcessorType;
        public uint dwAllocationGranularity;
        public uint dwProcessorLevel;
        public uint dwProcessorRevision;
    }

    [StructLayout(LayoutKind.Explicit)]
    public struct _PROCESSOR_INFO_UNION
    {
        [FieldOffset(0)]
        internal uint dwOemId;
        [FieldOffset(0)]
        internal ushort wProcessorArchitecture;
        [FieldOffset(2)]
        internal ushort wReserved;
    }
    }

    public class Program
    {
    public static void Main(string[] args)
    {
        WinApi.SYSTEM_INFO sysinfo = new WinApi.SYSTEM_INFO();
        WinApi.GetSystemInfo(ref sysinfo);
        Console.WriteLine("dwProcessorType ={0}", sysinfo.dwProcessorType.ToString());
        Console.WriteLine("dwPageSize      ={0}", sysinfo.dwPageSize.ToString());
    }
    }

}

Alternative Managed API:

Do you know one? Please contribute it!

Please edit this page!

Do you have...

• helpful tips or sample code to share for using this API in managed code?
• corrections to the existing content?
• variations of the signature you want to share?
• additional languages you want to include?

Select "Edit This Page" on the right hand toolbar and edit it! Or add new pages containing supporting types needed for this API (structures, delegates, and more).