winform调用API

简单的调用API用法：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsFormsApplication4
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        [DllImport("User32.dll")]
        public static extern int MessageBox(int h, string m, string c, int type);

        /// <summary>
        /// 系统信息
        /// </summary>
        [StructLayout(LayoutKind.Sequential)]
        public struct SYSTEM_INFO
        {
            public uint dwOemId;
            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;
        }

        /// <summary>
        /// 内存信息
        /// </summary>
        [StructLayout(LayoutKind.Sequential)]
        public struct MEMORYSTATUS
        {
            public uint dwLength;
            public uint dwMemoryLoad;
            public uint dwTotalPhys;
            public uint dwAvailPhys;
            public uint dwTotalPageFile;
            public uint dwAvailPageFile;
            public uint dwTotalVirtual;
            public uint dwAvailVirtual;
        }

        //获取系统信息
        [DllImport("kernel32")]
        static extern void GetSystemInfo(ref SYSTEM_INFO pSI);
        //获取内存信息
        [DllImport("kernel32")]
        static extern void GlobalMemoryStatus(ref MEMORYSTATUS buf);

        private void button1_Click(object sender, EventArgs e)
        {
            //MessageBox(0, "API Message Box", "API Demo", 0);
            SYSTEM_INFO sys = new SYSTEM_INFO();
            GetSystemInfo(ref sys);
            MessageBox(0, sys.dwProcessorType.ToString(), "系统信息测试", 0);
        }
    }
}