Сайт о программировании, с примерами программ на C# Java

Класс шифрования C#

Этот класс упрощает быстрое шифрование данных паролем с помощью встроенных функций .NET Framework.

using System.Text;
using System.Security.Cryptography;
using System.IO;

class Encryptor
{
    public static byte[] Encrypt(byte[] input, string password)
    {
        try
        {
            TripleDESCryptoServiceProvider service = new TripleDESCryptoServiceProvider();
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

            byte[] key = md5.ComputeHash(Encoding.ASCII.GetBytes(password));
            byte[] iv = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

            return Transform(input, service.CreateEncryptor(key, iv));
        }
        catch (Exception)
        {
            return new byte[0];
        }
    }

    public static byte[] Decrypt(byte[] input, string password)
    {
        try
        {
            TripleDESCryptoServiceProvider service = new TripleDESCryptoServiceProvider();
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

            byte[] key = md5.ComputeHash(Encoding.ASCII.GetBytes(password));
            byte[] iv = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

            return Transform(input, service.CreateDecryptor(key, iv));
        }
        catch (Exception)
        {
            return new byte[0];
        }
    }

    public static string Encrypt(string text, string password)
    {
        byte[] input = Encoding.UTF8.GetBytes(text);
        byte[] output = Encrypt(input, password);
        return Convert.ToBase64String(output);
    }

    public static string Decrypt(string text, string password)
    {
        byte[] input = Convert.FromBase64String(text);
        byte[] output = Decrypt(input, password);
        return Encoding.UTF8.GetString(output);
    }

    private static byte[] Transform(byte[] input, ICryptoTransform CryptoTransform)
    {
        MemoryStream memStream = new MemoryStream();
        CryptoStream cryptStream = new CryptoStream(memStream, CryptoTransform, CryptoStreamMode.Write);

        cryptStream.Write(input, 0, input.Length);
        cryptStream.FlushFinalBlock();

        memStream.Position = 0;
        byte[] result = new byte[Convert.ToInt32(memStream.Length)];
        memStream.Read(result, 0, Convert.ToInt32(result.Length));

        memStream.Close();
        cryptStream.Close();

        return result;
    }
}

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using System.Text;

using System.Security.Cryptography;

using System.IO;

class Encryptor

{

public static byte[] Encrypt(byte[] input, string password)

{

try

{

TripleDESCryptoServiceProvider service = new TripleDESCryptoServiceProvider();

MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

byte[] key = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

byte[] iv = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

return Transform(input, service.CreateEncryptor(key, iv));

}

catch (Exception)

{

return new byte[0];

}

public static byte[] Decrypt(byte[] input, string password)

{

try

{

TripleDESCryptoServiceProvider service = new TripleDESCryptoServiceProvider();

MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

byte[] key = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

byte[] iv = md5.ComputeHash(Encoding.ASCII.GetBytes(password));

return Transform(input, service.CreateDecryptor(key, iv));

}

catch (Exception)

{

return new byte[0];

}

public static string Encrypt(string text, string password)

{

byte[] input = Encoding.UTF8.GetBytes(text);

byte[] output = Encrypt(input, password);

return Convert.ToBase64String(output);

}

public static string Decrypt(string text, string password)

{

byte[] input = Convert.FromBase64String(text);

byte[] output = Decrypt(input, password);

return Encoding.UTF8.GetString(output);

}

private static byte[] Transform(byte[] input, ICryptoTransform CryptoTransform)

{

MemoryStream memStream = new MemoryStream();

CryptoStream cryptStream = new CryptoStream(memStream, CryptoTransform, CryptoStreamMode.Write);

cryptStream.Write(input, 0, input.Length);

cryptStream.FlushFinalBlock();

memStream.Position = 0;

byte[] result = new byte[Convert.ToInt32(memStream.Length)];

memStream.Read(result, 0, Convert.ToInt32(result.Length));

memStream.Close();

cryptStream.Close();

return result;

}

Экспорт данные в CSV C#

Простой метод записи данных в формате DataTable или DataView на C# в CSV-файл.

using System;
using System.Data;
using System.Windows.Forms;
using System.IO;

private void ExportDatatviewToCsv(string iFilename, DataView dv)
{
    // Open output stream
    StreamWriter swFile = new StreamWriter(iFilename);

    // Header
    string[] colLbls = new string[dv.Table.Columns.Count];
    for (int i = 0; i < dv.Table.Columns.Count; i++)
    {
        colLbls[i] = dv.Table.Columns[i].ColumnName;
        colLbls[i] = GetWriteableValueForCsv(colLbls[i]);
    }

    // Write labels
    swFile.WriteLine(string.Join(",", colLbls));

    // Rows of Data
    foreach (DataRowView rowData in dv)
    {
        string[] colData = new string[dv.Table.Columns.Count];
        for (int i = 0; i < dv.Table.Columns.Count; i++)
        {
            object obj = rowData[i];
            colData[i] = GetWriteableValueForCsv(obj);
        }

        // Write data in row
        swFile.WriteLine(string.Join(",", colData));
    }

    // Close output stream
    swFile.Close();
}

private void ExportDatatableToCsv(string iFilename, DataTable dt)
{
    // Open output stream
    StreamWriter swFile = new StreamWriter(iFilename);

    // Header
    string[] colLbls = new string[dt.Columns.Count];

    for (int i = 0; i < dt.Columns.Count; i++)
    {
        colLbls[i] = dt.Columns[i].ColumnName;
        colLbls[i] = GetWriteableValueForCsv(colLbls[i]);
    }

    // Write labels
    swFile.WriteLine(string.Join(",", colLbls));

    // Rows of Data
    foreach (DataRow rowData in dt.Rows)
    {
        string[] colData = new string[dt.Columns.Count];

        for (int i = 0; i < dt.Columns.Count; i++)
        {
            object obj = rowData[i];
            colData[i] = GetWriteableValueForCsv(obj);
        }

        // Write data in row
        swFile.WriteLine(string.Join(",", colData));
    }

    // Close output stream
    swFile.Close();
}

public static string GetWriteableValueForCsv(object obj)
{
    // Nullable types to blank
    if (obj == null || obj == Convert.DBNull)
        return "";

    // if string has no ','
    if (obj.ToString().IndexOf(",") == -1)
        return obj.ToString();

    // remove backslahes
    return "\"" + obj.ToString() + "\"";
}

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using System;

using System.Data;

using System.Windows.Forms;

using System.IO;

private void ExportDatatviewToCsv(string iFilename, DataView dv)

{

// Open output stream

StreamWriter swFile = new StreamWriter(iFilename);

// Header

string[] colLbls = new string[dv.Table.Columns.Count];

for (int i = 0; i < dv.Table.Columns.Count; i++)

{

colLbls[i] = dv.Table.Columns[i].ColumnName;

colLbls[i] = GetWriteableValueForCsv(colLbls[i]);

}

// Write labels

swFile.WriteLine(string.Join(",", colLbls));

// Rows of Data

foreach (DataRowView rowData in dv)

{

string[] colData = new string[dv.Table.Columns.Count];

for (int i = 0; i < dv.Table.Columns.Count; i++)

{

object obj = rowData[i];

colData[i] = GetWriteableValueForCsv(obj);

}

// Write data in row

swFile.WriteLine(string.Join(",", colData));

}

// Close output stream

swFile.Close();

}

private void ExportDatatableToCsv(string iFilename, DataTable dt)

{

// Open output stream

StreamWriter swFile = new StreamWriter(iFilename);

// Header

string[] colLbls = new string[dt.Columns.Count];

for (int i = 0; i < dt.Columns.Count; i++)

{

colLbls[i] = dt.Columns[i].ColumnName;

colLbls[i] = GetWriteableValueForCsv(colLbls[i]);

}

// Write labels

swFile.WriteLine(string.Join(",", colLbls));

// Rows of Data

foreach (DataRow rowData in dt.Rows)

{

string[] colData = new string[dt.Columns.Count];

for (int i = 0; i < dt.Columns.Count; i++)

{

object obj = rowData[i];

colData[i] = GetWriteableValueForCsv(obj);

}

// Write data in row

swFile.WriteLine(string.Join(",", colData));

}

// Close output stream

swFile.Close();

}

public static string GetWriteableValueForCsv(object obj)

{

// Nullable types to blank

if (obj == null || obj == Convert.DBNull)

return "";

// if string has no ','

if (obj.ToString().IndexOf(",") == -1)

return obj.ToString();

// remove backslahes

return "\"" + obj.ToString() + "\"";

}

Создание скриншотов с помощью C #

Код использует GDI в C#.NET для рисования основного экрана на растровом изображении.

public class API
{
    [DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
    public static extern IntPtr GetDC(IntPtr hWnd);

    [DllImport("user32.dll", ExactSpelling = true)]
    public static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);

    [DllImport("gdi32.dll", ExactSpelling = true)]
    public static extern IntPtr BitBlt(IntPtr hDestDC, int x, int y, int nWidth, int nHeight, IntPtr hSrcDC, int xSrc, int ySrc, int dwRop);

    [DllImport("user32.dll", EntryPoint = "GetDesktopWindow")]
    public static extern IntPtr GetDesktopWindow();
}

internal class ScreenShot
{
    public static Bitmap Take()
    {
        int screenWidth = Screen.PrimaryScreen.Bounds.Width;
        int screenHeight = Screen.PrimaryScreen.Bounds.Height;

        Bitmap screenBmp = new Bitmap(screenWidth, screenHeight);
        Graphics g = Graphics.FromImage(screenBmp);

        IntPtr dc1 = API.GetDC(API.GetDesktopWindow());
        IntPtr dc2 = g.GetHdc();

        //Основной эскиз, копирует экран в растровое изображение
        //последнее число — константа копирования
        API.BitBlt(dc2, 0, 0, screenWidth, screenHeight, dc1, 0, 0, 13369376);

        //Clean up
        API.ReleaseDC(API.GetDesktopWindow(), dc1);
        g.ReleaseHdc(dc2);
        g.Dispose();

        return screenBmp;
    }
}

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public class API

{

[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]

public static extern IntPtr GetDC(IntPtr hWnd);

[DllImport("user32.dll", ExactSpelling = true)]

public static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);

[DllImport("gdi32.dll", ExactSpelling = true)]

public static extern IntPtr BitBlt(IntPtr hDestDC, int x, int y, int nWidth, int nHeight, IntPtr hSrcDC, int xSrc, int ySrc, int dwRop);

[DllImport("user32.dll", EntryPoint = "GetDesktopWindow")]

public static extern IntPtr GetDesktopWindow();

}

internal class ScreenShot

{

public static Bitmap Take()

{

int screenWidth = Screen.PrimaryScreen.Bounds.Width;

int screenHeight = Screen.PrimaryScreen.Bounds.Height;

Bitmap screenBmp = new Bitmap(screenWidth, screenHeight);

Graphics g = Graphics.FromImage(screenBmp);

IntPtr dc1 = API.GetDC(API.GetDesktopWindow());

IntPtr dc2 = g.GetHdc();

//Основной эскиз, копирует экран в растровое изображение

//последнее число — константа копирования

API.BitBlt(dc2, 0, 0, screenWidth, screenHeight, dc1, 0, 0, 13369376);

//Clean up

API.ReleaseDC(API.GetDesktopWindow(), dc1);

g.ReleaseHdc(dc2);

g.Dispose();

return screenBmp;

}

Вычисляет угол, под которым точка находится к началу координат и обратно C#

Используя простую математику, мы можем преобразовать между углами (в градусах) и точками координат XY. Полезно при работе с элементами круга.

/// <summary>
/// Вычисляет точку, находящуюся под углом от начала координат (0 справа)
/// </summary>
private PointF DegreesToXY(float degrees, float radius, Point origin)
{
    PointF xy = new PointF();
    double radians = degrees * Math.PI / 180.0;

    xy.X = (float)Math.Cos(radians) * radius + origin.X;
    xy.Y = (float)Math.Sin(-radians) * radius + origin.Y;

    return xy;
}

/// <summary>
/// Вычисляет угол, под которым точка находится к началу координат (0 справа)
/// </summary>
private float XYToDegrees(Point xy, Point origin)
{
    int deltaX = origin.X - xy.X;
    int deltaY = origin.Y - xy.Y;

    double radAngle = Math.Atan2(deltaY, deltaX);
    double degreeAngle = radAngle * 180.0 / Math.PI;

    return (float)(180.0 - degreeAngle);
}

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/// <summary>

/// Вычисляет точку, находящуюся под углом от начала координат (0 справа)

/// </summary>

private PointF DegreesToXY(float degrees, float radius, Point origin)

{

PointF xy = new PointF();

double radians = degrees * Math.PI / 180.0;

xy.X = (float)Math.Cos(radians) * radius + origin.X;

xy.Y = (float)Math.Sin(-radians) * radius + origin.Y;

return xy;

}

/// <summary>

/// Вычисляет угол, под которым точка находится к началу координат (0 справа)

/// </summary>

private float XYToDegrees(Point xy, Point origin)

{

int deltaX = origin.X - xy.X;

int deltaY = origin.Y - xy.Y;

double radAngle = Math.Atan2(deltaY, deltaX);

double degreeAngle = radAngle * 180.0 / Math.PI;

return (float)(180.0 - degreeAngle);

}

Как удалить программе саму себя? C#

Для этого используем пакетный сценарий, который он создает для удаления исполняемого файла, а затем удаляет себя сам.

using System.Diagnostics;
using System.IO;
static private void DeleteSelf()
{
    //Use this line if your running from console
    //string pa = Process.GetCurrentProcess().MainModule.FileName;

    //Use this line if your running from Windows Form
    string pa = Application.StartupPath;
    string bf = "@echo off" + Environment.NewLine + 
                ":dele" + Environment.NewLine + 
                "del \"" + pa + "\"" + Environment.NewLine + 
                "if Exist \"" + pa + "\" GOTO dele" + Environment.NewLine + 
                "del %0";

    //string filename = RandomString(RandomNumber(5, 15)) + ".bat";
    string filename = Path.GetRandomFileName() + ".bat";

    StreamWriter file = new StreamWriter(Environment.GetEnvironmentVariable("TMP") + filename);
    file.Write(bf);
    file.Close();

    Process proc = new Process();
    proc.StartInfo.FileName = Environment.GetEnvironmentVariable("TMP") + filename;
    proc.StartInfo.CreateNoWindow = true;
    proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
    proc.StartInfo.UseShellExecute = true;

    proc.Start();
    proc.PriorityClass = ProcessPriorityClass.Normal;
}

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using System.Diagnostics;

using System.IO;

static private void DeleteSelf()

{

//Use this line if your running from console

//string pa = Process.GetCurrentProcess().MainModule.FileName;

//Use this line if your running from Windows Form

string pa = Application.StartupPath;

string bf = "@echo off" + Environment.NewLine +

":dele" + Environment.NewLine +

"del \"" + pa + "\"" + Environment.NewLine +

"if Exist \"" + pa + "\" GOTO dele" + Environment.NewLine +

"del %0";

//string filename = RandomString(RandomNumber(5, 15)) + ".bat";

string filename = Path.GetRandomFileName() + ".bat";

StreamWriter file = new StreamWriter(Environment.GetEnvironmentVariable("TMP") + filename);

file.Write(bf);

file.Close();

Process proc = new Process();

proc.StartInfo.FileName = Environment.GetEnvironmentVariable("TMP") + filename;

proc.StartInfo.CreateNoWindow = true;

proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;

proc.StartInfo.UseShellExecute = true;

proc.Start();

proc.PriorityClass = ProcessPriorityClass.Normal;

}