技巧杂项

 

压缩 :
using System.IO;
using System.IO.Compression;
………………………………………
        public byte[] Zip(byte[] byteArray)   //压缩方法
        ...{
               MemoryStream memoryStream = new MemoryStream();
               DeflateStream deflateStream = new DeflateStream(memoryStream, CompressionMode.Compress,false);
               deflateStream.Write(byteArray, 0, byteArray.Length);
               deflateStream.Close();
               return memoryStream.ToArray();
        }

        public byte[] Dezip(byte[] byteArray)   //解压缩方法
        ...{
            MemoryStream memoryStream = new MemoryStream(byteArray); 

             这节主要是要获取解压后的大小, 要改进#region 这节主要是要获取解压后的大小, 要改进
            DeflateStream deflateStreamSize = new DeflateStream(memoryStream, CompressionMode.Decompress,false);
            int i = new int();
            i = 0;
            while (deflateStreamSize.ReadByte() != -1)
            ...{
                i = i + 1;
            }           
            #endregion

            byte[] dezipArray = new byte[i];             
            memoryStream.Position = 0;  //将流的位置重新移到开始位置
            DeflateStream deflateStream = new DeflateStream(memoryStream, CompressionMode.Decompress, false);            
            
            deflateStream.Read(dezipArray, 0, dezipArray.Length);         

            deflateStream.Close();
            return dezipArray;
        }


        private void button1_Click(object sender, EventArgs e)
        ...{
            OpenFileDialog openFileDialog = new OpenFileDialog();
            openFileDialog.ShowDialog();
            openFileDialog.Multiselect = false;
            if (!string.IsNullOrEmpty(openFileDialog.FileName))
            ...{         
                //下面可改为取出已压缩好的字节数组解压缩之后,保存;       
                byte[] byteArray =File.ReadAllBytes(openFileDialog.FileName);

                byte[] zipByte=Zip(byteArray);

                byte[] deZipByte=Dezip(zipByte); 
                MessageBox.Show("compression before: " + (byteArray.Length / 1024).ToString() + " " + "compression after: " + (tempByte.Length / 1024).ToString()+" "
                                 + "Decompression after: " + (detempByte.Length/1024).ToString());
                File.WriteAllBytes(@"c:a.zip", zipByte); //保存压缩后的文件
                File.WriteAllBytes(@"c:a.xlt", deZipByte); //保存解压缩后的文件                
            }           
        }



线程调用和绘图:
在创建托管的线程时，在该线程上执行的方法将通过一个传递给 Thread 构造函数的 ThreadStart 委托或 ParameterizedThreadStart 委托来表示。在调用 System.Threading.Thread.Start 方法之前，该线程不会开始执行。执行将从 ThreadStart 或 ParameterizedThreadStart 委托表示的方法的第一行开始。区别是ThreadStart执行不带参数的委托方法， ParameterizedThreadStart执行带参数的委托方法。
A． ThreadStart执行不带参数的委托方法实例：
using System.Drawing.Drawing2D;
using System.Threading;
………………………………………..
        private void button3_Click(object sender, EventArgs e)
        ...{
           //调用线程
            Thread thread = new Thread(new ThreadStart(this.BrushRectangle));
           //如果线程中的方法有使用到多线程,如openFileDialog.ShowDialog();则必须在线程开始前将线程设为单线程;
            thread.SetApartmentState(ApartmentState.STA); // ApartmentState.STA 单线程, ApartmentState.MTA 多线程
            thread.Start();
        }

        public void BrushRectangle()  //绘图
        ...{
            int x;
            int y;
            int width;
            int height;
            Rectangle rectangle = new Rectangle(10, 10, 450, 25);
            
            LinearGradientBrush rectangleBrush = new LinearGradientBrush(rectangle, Color.AliceBlue, Color.CornflowerBlue, LinearGradientMode.ForwardDiagonal);
            Pen rectanglePen = new Pen(rectangleBrush);
            Graphics g = this.CreateGraphics();
            x=rectangle.X;
            y=rectangle.Y;
            width=rectangle.Width/100;
            height=rectangle.Height;          
            
            for (int i = 1; i <= 100; i++)
            ...{
                g.FillRectangle(rectangleBrush, x * i, y, width, height);
                Thread.Sleep(50);
            }
            MessageBox.Show("Ok");


            //下面演示如何生成图片的缩略图；
           System.Drawing.Image image = System.Drawing.Image.FromStream(FileUpload1.PostedFile.InputStream, true, true);
                    Bitmap myBitmap = new System.Drawing.Bitmap(image); 
                   Image.GetThumbnailImageAbort myCallback = new Image.GetThumbnailImageAbort(ThumbnailCallback);
                   Image myThumbnail = myBitmap.GetThumbnailImage(40, 40, myCallback, IntPtr.Zero);
                   Graphics g = this.CreateGraphics();  
g.DrawImage(myThumbnail, 250, 175);
        }

B．ParameterizedThreadStart执行带参数的委托方法的实例：
using System;
using System.Threading;

public class Work
...{
    public static void Main()
    ...{
        // To start a thread using a shared thread procedure, use
        // the class name and method name when you create the 
        // ParameterizedThreadStart delegate.
        //
        Thread newThread = new Thread(
            new ParameterizedThreadStart(Work.DoWork));
        
        // Use the overload of the Start method that has a
        // parameter of type Object. You can create an object that
        // contains several pieces of data, or you can pass any 
        // reference type or value type. The following code passes
        // the integer value 42.
        //
        newThread.Start(42);

        // To start a thread using an instance method for the thread 
        // procedure, use the instance variable and method name when 
        // you create the ParameterizedThreadStart delegate.
        //
        Work w = new Work();
        newThread = new Thread(
            new ParameterizedThreadStart(w.DoMoreWork));
        
        // Pass an object containing data for the thread.
        //
        newThread.Start("The answer.");
    }
 
    public static void DoWork(object data)
    ...{
        Console.WriteLine("Static thread procedure. Data='{0}'",data);
    }

    public void DoMoreWork(object data)
    ...{
        Console.WriteLine("Instance thread procedure. Data='{0}'",data);
    }
}

/**//* This code example produces the following output (the order 
   of the lines might vary):

Static thread procedure. Data='42'
Instance thread procedure. Data='The answer'
*/




发送邮件:
using System.Net.Mail;
……………………

            try
            ...{
                MailAddress mailAddressFrom = new MailAddress("your mail address");
                MailAddress mailAddressTo = new MailAddress("your mail address");

                MailMessage mailMessage = new MailMessage(mailAddressFrom, mailAddressTo);
                mailMessage.Body = "This is Mail Body!";
                mailMessage.Subject = "This is Mail Subject!";

                //增加附件;
                OpenFileDialog of = new OpenFileDialog();
                of.Multiselect = true;
                of.ShowDialog();
                if (of.FileNames.Length >0)
                ...{
                    foreach (string filename in of.FileNames)
                    ...{
                        Attachment at = new Attachment(filename);
                        mailMessage.Attachments.Add(at);
                    }
                }

                SmtpClient smtpClient = new SmtpClient("smtp name");                
                smtpClient.Credentials = new System.Net.NetworkCredential("username", "your password");
                smtpClient.Send(mailMessage);               
                
                MessageBox.Show("Send Mail Successfully!");
            }
            catch(SmtpException ex)
            ...{
                throw new Exception(ex.StatusCode.ToString());
            }

对象管理:
using System.Management;
………………………
            //列出所有服务
            ManagementObjectSearcher searcher = new
            ManagementObjectSearcher("Select * from win32_service where State='Running'");
            listBox1.Items.Clear();
            foreach (ManagementObject svc in searcher.Get())
            ...{
               listBox1.Items.Add(svc["DisplayName"].ToString());
            }


读取系统日志:
using System.Diagnostics;
……………………..
            EventLog eventLog = new EventLog("Application", ".");            

            foreach (EventLogEntry eventLogEntry in eventLog.Entries)
            ...{
                if (eventLogEntry.Source == "MSSQLServer")
                ...{
                    if (eventLogEntry.EntryType == EventLogEntryType.Error ||
                        eventLogEntry.EntryType == EventLogEntryType.Warning)
                    ...{
                        listBox1.Items.Add(eventLogEntry.Message);
                    }
                }
            }







获取网络及驱动器信息:
using System.IO;  //驱动器
using System.Net.NetworkInformation;  //网络
………………………
            listBox1.Items.Clear();
            DriveInfo[] driveInfoArrary = DriveInfo.GetDrives();
            foreach (DriveInfo driveInfo in driveInfoArrary)
            ...{
                listBox1.Items.Add(driveInfo.Name);
            }

            NetworkInterface[] networkInterfaceArray = NetworkInterface.GetAllNetworkInterfaces();
            foreach (NetworkInterface networkInterface in networkInterfaceArray)
            ...{
                listBox1.Items.Add(networkInterface.Name + "{" + networkInterface.GetIPv4Statistics().BytesReceived.ToString() + "}");
            }


DLL调用:
using System.Runtime.InteropServices;
……………………………………………..
           // CharSet=CharSet.Unicode表示传输字符的格式,不加将会出现乱码
        [DllImport("User32.dll",CharSet=CharSet.Unicode)]
        public static extern int MessageBoxW(int h, string m, string c, int type);
         ………………………………….
        private void button1_Click(object sender, EventArgs e)
        ...{
           MessageBoxW(0, "显示消息的地方", "主题", 0);
        }

正则表达式调用实例：
        private  bool IsInteger(string strNumber)
        ...{
            Regex objNotIntPattern = new Regex("[^0-9-]");
            Regex objIntPattern = new Regex("^-[0-9]+$|^[0-9]+$");
            return !objNotIntPattern.IsMatch(strNumber) &&
                    objIntPattern.IsMatch(strNumber);
        }