C#获取计算机物理内存和可用内存大小封装类SystemInfo

背景

在程序开发中经常会根据物理内存和可用内存大小的不用而执行不同的逻辑，尤其是在执行大数据量处理时，如果不做可用内存预判很容易出现内存溢出的情况，本文就分享一下在C#中如何获取计算机物理内存大小和可用内存大小的方法。

代码实现

SystemInfo.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
using System.Management;
using System.Runtime.InteropServices;

namespace Wongoing.Basic
{ 
    ///  
    /// 系统信息类 - 获取CPU、内存、磁盘、进程信息 
    ///  
    public class SystemInfo
    {
        #region 字段定义

        private int m_ProcessorCount = 0;   //CPU个数 
        private PerformanceCounter pcCpuLoad;   //CPU计数器 
        private long m_PhysicalMemory = 0;   //物理内存 

        private const int GW_HWNDFIRST = 0;
        private const int GW_HWNDNEXT = 2;
        private const int GWL_STYLE = (-16);
        private const int WS_VISIBLE = 268435456;
        private const int WS_BORDER = 8388608;

        #endregion

        #region AIP声明

        [DllImport("IpHlpApi.dll")]
        extern static public uint GetIfTable(byte[] pIfTable, ref uint pdwSize, bool bOrder);

        [DllImport("User32")]
        private extern static int GetWindow(int hWnd, int wCmd);

        [DllImport("User32")]
        private extern static int GetWindowLongA(int hWnd, int wIndx);

        [DllImport("user32.dll")]
        private static extern bool GetWindowText(int hWnd, StringBuilder title, int maxBufSize);

        [DllImport("user32", CharSet = CharSet.Auto)]
        private extern static int GetWindowTextLength(IntPtr hWnd);

        #endregion

        #region 单例实现

        private static SystemInfo _instance = null;

        #region 构造函数
        ///  
        /// 构造函数，初始化计数器等 
        ///  
        private SystemInfo()
        {
            初始化CPU计数器 
            //pcCpuLoad = new PerformanceCounter("Processor", "% Processor Time", "_Total");
            //pcCpuLoad.MachineName = ".";
            //pcCpuLoad.NextValue();

            CPU个数 
            //m_ProcessorCount = Environment.ProcessorCount; 

            //获得物理内存 
            ManagementClass mc = new ManagementClass("Win32_ComputerSystem");
            ManagementObjectCollection moc = mc.GetInstances();
            foreach (ManagementObject mo in moc)
            {
                if (mo["TotalPhysicalMemory"] != null)
                {
                    m_PhysicalMemory = long.Parse(mo["TotalPhysicalMemory"].ToString());
                }
            }
        }
        #endregion

        /// 

        /// 静态实例
        /// 
        public static SystemInfo Instance
        {
            get
            {
                lock ("SystemInfo")
                {
                    if (_instance == null)
                    {
                        _instance = new SystemInfo();
                    }
                    return _instance;
                }
            }
        }

        #endregion

        #region CPU个数

        ///  
        /// 获取CPU个数 
        ///  
        public int ProcessorCount
        {
            get
            {
                return m_ProcessorCount;
            }
        }

        #endregion

        #region CPU占用率

        ///  
        /// 获取CPU占用率 
        ///  
        public float CpuLoad
        {
            get
            {
                return pcCpuLoad.NextValue();
            }
        }

        #endregion

        #region 可用内存

        ///  
        /// 获取可用内存 
        ///  
        public long MemoryAvailable
        {
            get
            {
                long availablebytes = 0;
                //ManagementObjectSearcher mos = new ManagementObjectSearcher("SELECT * FROM Win32_PerfRawData_PerfOS_Memory"); 
                //foreach (ManagementObject mo in mos.Get()) 
                //{ 
                //    availablebytes = long.Parse(mo["Availablebytes"].ToString()); 
                //} 
                ManagementClass mos = new ManagementClass("Win32_OperatingSystem");
                foreach (ManagementObject mo in mos.GetInstances())
                {
                    if (mo["FreePhysicalMemory"] != null)
                    {
                        availablebytes = 1024 * long.Parse(mo["FreePhysicalMemory"].ToString());
                    }
                }
                return availablebytes;
            }
        }

        #endregion

        #region 物理内存

        ///  
        /// 获取物理内存 
        ///  
        public long PhysicalMemory
        {
            get
            {
                return m_PhysicalMemory;
            }
        }

        #endregion 
    } 
}

调用代码

double available = SystemInfo.Instance.MemoryAvailable / 1024.0 / 1024.0 / 1014.0;                          //可用内存
double used = (SystemInfo.Instance.PhysicalMemory - SystemInfo.Instance.MemoryAvailable) / 1024.0 / 1024.0 / 1024.0;    //已用内存
double physicalMemory = SystemInfo.Instance.PhysicalMemory / 1024.0 / 1024.0 / 1024.0;                      //物理内存总量
Console.WriteLine("可用内存：" + String.Format("{0:f2}GB", available));
Console.WriteLine("物理内存：" + String.Format("{0:f2}GB", physicalMemory));
Console.WriteLine("内存用比：" + String.Format("{0:f2}/{1:f2}GB({2:f0}%)", used, physicalMemory, (SystemInfo.Instance.PhysicalMemory - SystemInfo.Instance.MemoryAvailable) * 100.0 / SystemInfo.Instance.PhysicalMemory));

运行结果

运行结果如下图：