C# 实用代码段

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;
namespace notifyIconShow
{
 public partial class notifyIconShow : Form
 {
  public notifyIconShow()
  {
   InitializeComponent();
  }
  #region//设置鼠标放在托盘图标上面的文字
  /// <summary>
  /// 方法名称：notifyIconShow_Load(窗体加载事件)
  /// 方法作用：设置鼠标放在托盘图标上面的文字
  /// 完成日期：2010年5月16日
  /// 作者：心语
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void notifyIconShow_Load(object sender, EventArgs e)
  {
   //设置鼠标放在托盘图标上面的文字
   this.notifyIcon1.Text = "心语托盘图标";
  }
  #endregion
  #region//创建对象及声明变量
  //创建NotifyIcon对象
  NotifyIcon notifyicon = new NotifyIcon();
  //创建托盘图标对象
  Icon ico = new Icon("Clock2.ico");
  //创建托盘菜单对象
  ContextMenu notifyContextMenu = new ContextMenu();
  #endregion
  #region//隐藏任务栏图标，显示托盘图标
  /// <summary>
  /// 方法名称：notifyIconShow_SizeChanged(窗体大小改变后事件)
  /// 方法作用：隐藏任务栏图标，显示托盘图标
  /// 完成日期：2010年5月16日
  /// 作者：心语
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void notifyIconShow_SizeChanged(object sender, EventArgs e)
  {
   //判断是否选择的是最小化按钮
   if (WindowState == FormWindowState.Minimized)
   {
    //托盘显示图标等于托盘图标对象
    //注意notifyIcon1是控件的名字而不是对象的名字
    notifyIcon1.Icon = ico;
    //隐藏任务栏区图标
    this.ShowInTaskbar = false;
    //图标显示在托盘区
    notifyicon.Visible = true;
   }
  }
  #endregion
  #region//还原窗体
  /// <summary>
  /// 方法名称：notifyIcon1_Click（托盘图标单击）
  /// 方法作用：还原窗体
  /// 完成日期：2010年5月16日
  /// 作者：心语
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void notifyIcon1_Click(object sender, EventArgs e)
  {
   //判断是否已经最小化于托盘
   if (WindowState == FormWindowState.Minimized)
   {
    //还原窗体显示
    WindowState = FormWindowState.Normal;
    //激活窗体并给予它焦点
    this.Activate();
    //任务栏区显示图标
    this.ShowInTaskbar = true;
    //托盘区图标隐藏
    notifyicon.Visible = false;
   }
  }
  #endregion
 }
}

在托盘显示图标

class Program
{
  static void Main(string[] args)
  {
   int n = m(, );
   System.Console.WriteLine("最小公倍数为:" + n.ToString());
   System.Console.Read();
  }
  static int f(int a, int b)//最大公约数
  {
   if (a < b) { a = a + b; b = a - b; a = a - b; }
   return (a % b == ) ? b : f(a % b, b);
  }
  static int m(int a, int b)//最小公倍数
  {
   return a * b / f(a, b);
  }
}

求最小公倍数

/// <summary>
/// 把汉字转换成拼音(全拼)
/// </summary>
/// <param name="hzString">汉字字符串</param>
/// <returns>转换后的拼音(全拼)字符串</returns>
public static string ConvertE(string hzString)
{
 // 匹配中文字符
 Regex regex = new Regex("^[\u4e00-\u9fa5]$");
 byte[] array = new byte[];
 string pyString = "";
 int chrAsc = ;
 int i1 = ;
 int i2 = ;
 char[] noWChar = hzString.ToCharArray();
 for (int j = ; j < noWChar.Length; j++)
 {
  // 中文字符
  if (regex.IsMatch(noWChar[j].ToString()))
  {
   array = System.Text.Encoding.Default.GetBytes(noWChar[j].ToString());
   i1 = (short)(array[]);
   i2 = (short)(array[]);
   chrAsc = i1 *  + i2 - ;
   if (chrAsc >  && chrAsc < )
   {
    pyString += noWChar[j];
   }
   else
   {
    // 修正部分文字
    if (chrAsc == -) // 修正“圳”字
     pyString += "Zhen";
    else
    {
     for (int i = (pyValue.Length - ); i >= ; i--)
     {
      if (pyValue[i] <= chrAsc)
      {
       pyString += pyName[i];
       break;
      }
     }
    }
   }
  }
  // 非中文字符
  else
  {
   pyString += noWChar[j].ToString();
  }
 }
 return pyString;
}
private static int[] pyValue = new int[]
{
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-, -,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-,
 -,-,-,-,-,-,-,-,-,-,-,-
};
private static string[] pyName = new string[]
{
 "A","Ai","An","Ang","Ao","Ba","Bai","Ban","Bang","Bao","Bei","Ben",
 "Beng","Bi","Bian","Biao","Bie","Bin","Bing","Bo","Bu","Ba","Cai","Can",
 "Cang","Cao","Ce","Ceng","Cha","Chai","Chan","Chang","Chao","Che","Chen","Cheng",
 "Chi","Chong","Chou","Chu","Chuai","Chuan","Chuang","Chui","Chun","Chuo","Ci","Cong",
 "Cou","Cu","Cuan","Cui","Cun","Cuo","Da","Dai","Dan","Dang","Dao","De",
 "Deng","Di","Dian","Diao","Die","Ding","Diu","Dong","Dou","Du","Duan","Dui",
 "Dun","Duo","E","En","Er","Fa","Fan","Fang","Fei","Fen","Feng","Fo",
 "Fou","Fu","Ga","Gai","Gan","Gang","Gao","Ge","Gei","Gen","Geng","Gong",
 "Gou","Gu","Gua","Guai","Guan","Guang","Gui","Gun","Guo","Ha","Hai","Han",
 "Hang","Hao","He","Hei","Hen","Heng","Hong","Hou","Hu","Hua","Huai","Huan",
 "Huang","Hui","Hun","Huo","Ji","Jia","Jian","Jiang","Jiao","Jie","Jin","Jing",
 "Jiong","Jiu","Ju","Juan","Jue","Jun","Ka","Kai","Kan","Kang","Kao","Ke",
 "Ken","Keng","Kong","Kou","Ku","Kua","Kuai","Kuan","Kuang","Kui","Kun","Kuo",
 "La","Lai","Lan","Lang","Lao","Le","Lei","Leng","Li","Lia","Lian","Liang",
 "Liao","Lie","Lin","Ling","Liu","Long","Lou","Lu","Lv","Luan","Lue","Lun",
 "Luo","Ma","Mai","Man","Mang","Mao","Me","Mei","Men","Meng","Mi","Mian",
 "Miao","Mie","Min","Ming","Miu","Mo","Mou","Mu","Na","Nai","Nan","Nang",
 "Nao","Ne","Nei","Nen","Neng","Ni","Nian","Niang","Niao","Nie","Nin","Ning",
 "Niu","Nong","Nu","Nv","Nuan","Nue","Nuo","O","Ou","Pa","Pai","Pan",
 "Pang","Pao","Pei","Pen","Peng","Pi","Pian","Piao","Pie","Pin","Ping","Po",
 "Pu","Qi","Qia","Qian","Qiang","Qiao","Qie","Qin","Qing","Qiong","Qiu","Qu",
 "Quan","Que","Qun","Ran","Rang","Rao","Re","Ren","Reng","Ri","Rong","Rou",
 "Ru","Ruan","Rui","Run","Ruo","Sa","Sai","San","Sang","Sao","Se","Sen",
 "Seng","Sha","Shai","Shan","Shang","Shao","She","Shen","Sheng","Shi","Shou","Shu",
 "Shua","Shuai","Shuan","Shuang","Shui","Shun","Shuo","Si","Song","Sou","Su","Suan",
 "Sui","Sun","Suo","Ta","Tai","Tan","Tang","Tao","Te","Teng","Ti","Tian",
 "Tiao","Tie","Ting","Tong","Tou","Tu","Tuan","Tui","Tun","Tuo","Wa","Wai",
 "Wan","Wang","Wei","Wen","Weng","Wo","Wu","Xi","Xia","Xian","Xiang","Xiao",
 "Xie","Xin","Xing","Xiong","Xiu","Xu","Xuan","Xue","Xun","Ya","Yan","Yang",
 "Yao","Ye","Yi","Yin","Ying","Yo","Yong","You","Yu","Yuan","Yue","Yun",
 "Za", "Zai","Zan","Zang","Zao","Ze","Zei","Zen","Zeng","Zha","Zhai","Zhan",
 "Zhang","Zhao","Zhe","Zhen","Zheng","Zhi","Zhong","Zhou","Zhu","Zhua","Zhuai","Zhuan",
 "Zhuang","Zhui","Zhun","Zhuo","Zi","Zong","Zou","Zu","Zuan","Zui","Zun","Zuo"
};

汉字转拼音

//导入该命名空间
using System.Diagnostice;
Stopwatch watch=new Stopwatch ();
watch.Start();
/*
此处为要计算的运行代码
*/
watch.Stop();
//获取当前实例测量得出的总运行时间（以毫秒为单位）
string time = watch.ElapsedMilliseconds.ToString();

计算代码运行时间

protected void Page_Load(object sender, EventArgs e)
{
    int m = System.DateTime.Today.Month;
    int y = System.DateTime.Today.Year;
    int d = System.DateTime.Today.Day;
    int weeks = getWeekDay(y, m, d);
    switch (weeks)
    {
      case :
        this.TextBox1.Text = "星期一";
        break;
      case :
        this.TextBox1.Text = "星期二";
        break;
      case :
        this.TextBox1.Text = "星期三";
        break;
      case :
        this.TextBox1.Text = "星期四";
        break;
      case :
        this.TextBox1.Text = "星期五";
        break;
      case :
        this.TextBox1.Text = "星期六";
        break;
      case :
        this.TextBox1.Text = "星期日";
        break;
    }
}
/// <summary>根据日期，获得星期几</summary>
/// <param name="y">年</param>
/// <param name="m">月</param>
/// <param name="d">日</param>
/// <returns>星期几，1代表星期一；7代表星期日</returns>
public static int getWeekDay(int y, int m, int d)
{
    if (m == ) m = ;
    if (m == ) m = ;
    int week = (d +  * m +  * (m + ) /  + y + y /  - y /  + y / ) %  + ;
    return week;
}

根据日期获取星期方法

/// <summary>
/// C# 删除文件夹
/// 用法： DeleteFolder(@"c:\\1");
/// </summary>
/// <param name="dir"></param>
private static void DeleteFolder(string dir)
{
  // 循环文件夹里面的内容
  foreach (string f in Directory.GetFileSystemEntries(dir))
  {
  // 如果是文件存在
  if (File.Exists(f))
  {
  FileInfo fi = new FileInfo(f);
  if (fi.Attributes.ToString().IndexOf("Readonly") != )
  {
  fi.Attributes = FileAttributes.Normal;
  }
  // 直接删除其中的文件
  File.Delete(f);
  }
  else
  {
  // 如果是文件夹存在
  // 递归删除子文件夹
  DeleteFolder(f);
  }
  }
  // 删除已空文件夹
  Directory.Delete(dir);
}

删除文件夹的方法

OperatingSystem os = System.Environment.OSVersion;
Console.WriteLine(“Platform: {}”, os.Platform);
Console.WriteLine(“Service Pack: {}”, os.ServicePack);
Console.WriteLine(“Version: {}”, os.Version);
Console.WriteLine(“VersionString: {}”, os.VersionString);
Console.WriteLine(“CLR Version: {}”, System.Environment.Version); 

//在我的Windows 7系统中，输出以下信息
Platform: Win32NT
 Service Pack:
 Version: 6.1.7600.0
 VersionString: Microsoft Windows NT 6.1.7600.0
 CLR Version: 4.0.21006.1 

读取操作系统和CLR的版本

//可以通过Windows Management Instrumentation (WMI)提供的接口读取所需要的信息。
private static UInt32 CountPhysicalProcessors()
{
   ManagementObjectSearcher objects = new ManagementObjectSearcher(
    “SELECT * FROM Win32_ComputerSystem”);
   ManagementObjectCollection coll = objects.Get();
   foreach(ManagementObject obj in coll)
  {
    return (UInt32)obj[“NumberOfProcessors”];
  }
  return ;
}
private static UInt64 CountPhysicalMemory()
{
  ManagementObjectSearcher objects =new ManagementObjectSearcher(
   “SELECT * FROM Win32_PhysicalMemory”);
  ManagementObjectCollection coll = objects.Get();
  UInt64 total = ;
  foreach (ManagementObject obj in coll)
  {
    total += (UInt64)obj[“Capacity”];
  }
  return total;
} 

//请添加对程序集System.Management的引用，确保代码可以正确编译。
Console.WriteLine(“Machine: {}”, Environment.MachineName);
Console.WriteLine(“# of processors (logical): {}”, Environment.ProcessorCount);
Console.WriteLine(“# of processors (physical): {}” CountPhysicalProcessors());
Console.WriteLine(“RAM installed: {:N0} bytes”, CountPhysicalMemory());
Console.WriteLine(“Is OS -bit? {}”,  Environment.Is64BitOperatingSystem);
Console.WriteLine(“Is process -bit? {}”, Environment.Is64BitProcess);
Console.WriteLine(“Little-endian: {}”, BitConverter.IsLittleEndian);
foreach (Screen screen in System.Windows.Forms.Screen.AllScreens)
{
   Console.WriteLine(“Screen {}”, screen.DeviceName);
   Console.WriteLine(“\tPrimary {}”, screen.Primary);
   Console.WriteLine(“\tBounds: {}”, screen.Bounds);
   Console.WriteLine(“\tWorking Area: {}”,screen.WorkingArea);
   Console.WriteLine(“\tBitsPerPixel: {}”,screen.BitsPerPixel);
}

读取CPU数量，内存容量