Software Developer Blog

c# универсальные шаблоны

// Declare the generic class.
public class GenericList<T>
{
    void Add(T input) { }
}
class TestGenericList
{
    private class ExampleClass { }
    static void Main()
    {
        // Declare a list of type int.
        GenericList<int> list1 = new GenericList<int>();

        // Declare a list of type string.
        GenericList<string> list2 = new GenericList<string>();

        // Declare a list of type ExampleClass.
        GenericList<ExampleClass> list3 = new GenericList<ExampleClass>();
    }
}

c# Delete and copy files with replacing

string sourceDir = @"c:\current";
string backupDir = @"c:\archives\2008";

try
{
    string[] picList = Directory.GetFiles(sourceDir, "*.jpg");
    string[] txtList = Directory.GetFiles(sourceDir, "*.txt");

    // Copy picture files.
    foreach (string f in picList)
    {
        // Remove path from the file name.
        string fName = f.Substring(sourceDir.Length + 1);

        // Use the Path.Combine method to safely append the file name to the path.
        // Will overwrite if the destination file already exists.
        File.Copy(Path.Combine(sourceDir, fName), Path.Combine(backupDir, fName), true);
    }

    // Copy text files.
    foreach (string f in txtList)
    {

        // Remove path from the file name.
        string fName = f.Substring(sourceDir.Length + 1);

        try
        {
            // Will not overwrite if the destination file already exists.
            File.Copy(Path.Combine(sourceDir, fName), Path.Combine(backupDir, fName));
        }

        // Catch exception if the file was already copied.
        catch (IOException copyError)
        {
            Console.WriteLine(copyError.Message);
        }
    }

    // Delete source files that were copied.
    foreach (string f in txtList)
    {
        File.Delete(f);
    }
    foreach (string f in picList)
    {
        File.Delete(f);
    }
}

catch (DirectoryNotFoundException dirNotFound)
{
    Console.WriteLine(dirNotFound.Message);
}

C# how to copy all files in a folder

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
 
namespace CopyDir
{
    class Program
    {
        static void Main(string[] args)
        {
            string FromDir = @"c:\source";
            string ToDir = @"c:\destination";
            if (!Directory.Exists(ToDir))
 
                Directory.CreateDirectory(ToDir);
 
            string[] Files;
            Files = Directory.GetFileSystemEntries(FromDir);
 
            for (int k = 0; k < Files.Length; k++)
            {
                string FromFile = Path.GetFileName(Files[k]);
 
                FileAttributes FileAttr = File.GetAttributes(Files[k]);
 
                if ((FileAttr & FileAttributes.Directory)== FileAttributes.Directory)
                    continue;
 
                Console.WriteLine(FromFile);
 
        string arrival = ToDir + "\\" + FromFile;
        File.Copy(Files[k], arrival, true);
                 
            }
            Console.ReadLine();
         }
    }
}

C# MySQL read and insert in BLOB field

//Save
//-----------------------------------
MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

string SQL;
UInt32 FileSize;
byte[] rawData;
FileStream fs;

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

try
{
    fs = new FileStream(@"c:\image.png", FileMode.Open, FileAccess.Read);
    FileSize = fs.Length;

    rawData = new byte[FileSize];
    fs.Read(rawData, 0, FileSize);
    fs.Close();

    conn.Open();

    SQL = "INSERT INTO file VALUES(NULL, @FileName, @FileSize, @File)";

    cmd.Connection = conn;
    cmd.CommandText = SQL;
    cmd.Parameters.AddWithValue("@FileName", strFileName);
    cmd.Parameters.AddWithValue("@FileSize", FileSize);
    cmd.Parameters.AddWithValue("@File", rawData);

    cmd.ExecuteNonQuery();

    MessageBox.Show("File Inserted into database successfully!",
        "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);

    conn.Close();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
        "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}

//Read
//-------------------------------------------------------------------------

MySql.Data.MySqlClient.MySqlConnection conn;
MySql.Data.MySqlClient.MySqlCommand cmd;
MySql.Data.MySqlClient.MySqlDataReader myData;

conn = new MySql.Data.MySqlClient.MySqlConnection();
cmd = new MySql.Data.MySqlClient.MySqlCommand();

string SQL;
UInt32 FileSize;
byte[] rawData;
FileStream fs;

conn.ConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test;";

SQL = "SELECT file_name, file_size, file FROM file";

try
{
    conn.Open();

    cmd.Connection = conn;
    cmd.CommandText = SQL;

    myData = cmd.ExecuteReader();

    if (! myData.HasRows)
        throw new Exception("There are no BLOBs to save");

    myData.Read();

    FileSize = myData.GetUInt32(myData.GetOrdinal("file_size"));
    rawData = new byte[FileSize];

    myData.GetBytes(myData.GetOrdinal("file"), 0, rawData, 0, FileSize);

    fs = new FileStream(@"C:\newfile.png", FileMode.OpenOrCreate, FileAccess.Write);
    fs.Write(rawData, 0, FileSize);
    fs.Close();

    MessageBox.Show("File successfully written to disk!",
        "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);

    myData.Close();
    conn.Close();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message,
        "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}

c# How to work with ini files

using System;
using System.Runtime.InteropServices;
using System.Text;

namespace sIniFile
{
    /// <summary>
    /// Descrizione di riepilogo per IniFileClass.
    /// </summary>
    public class IniFileClass
    {
        private String IniFile = "";
        
        // Importazione dei metodi dalle DLL di sistema
        [DllImport("kernel32")] private static extern long WritePrivateProfileInt(String Section, String Key, int Value, String FilePath);
        [DllImport("kernel32")] private static extern long WritePrivateProfileString(String Section, String Key, String Value, String FilePath);
        [DllImport("kernel32")] private static extern int GetPrivateProfileInt(String Section, String Key, int Default, String FilePath);
        [DllImport("kernel32")] private static extern int GetPrivateProfileString(String Section, String Key, String Default, StringBuilder retVal, int Size, String FilePath);

        public IniFileClass(String IniFile)
        {
            // Mi salvo il percorso del file INI
            this.IniFile = IniFile;
        }

        public String ReadString(String Section, String Key, String Default)
        {
            // Creo lo StringBuilder che conterra la stringa
            StringBuilder StrBu = new StringBuilder(255);
            // Provo a leggere il parametro richiesto
            GetPrivateProfileString(Section, Key, Default, StrBu, 255, IniFile);
            // Restituisco il parametro letto
            return StrBu.ToString();
        }

        public int ReadInt(String Section, String Key, int Default)
        {
            // Restituisco il valore del parametro letto
            return GetPrivateProfileInt(Section, Key, Default, IniFile); 
        }

        public void WriteString(String Section, String Key, String Value)
        {
            // Salvo il valore del parametro impostato
            WritePrivateProfileString(Section, Key, Value, IniFile);
        }

        public void WriteInt(String Section, String Key, int Value)
        {
            // Salvo il valore del parametro impostato
            WritePrivateProfileInt(Section, Key, Value, IniFile);
        }
    }
}

c# scroll panel with picturebox by dragging mouse

private Point _StartPoint;
void pictureBox1_MouseDown(object sender, MouseEventArgs e) {
  if (e.Button == MouseButtons.Left)
    _StartPoint = e.Location;
}
void pictureBox1_MouseMove(object sender, MouseEventArgs e) {
  if (e.Button == MouseButtons.Left) {
    Point changePoint = new Point(e.Location.X - _StartPoint.X, 
                                  e.Location.Y - _StartPoint.Y);
    panel1.AutoScrollPosition = new Point(-panel1.AutoScrollPosition.X - changePoint.X,
                                          -panel1.AutoScrollPosition.Y - changePoint.Y);
  }
}

c# create image with transparent background / c# Создание изображения с прозрачным бэкграундом

1)Use Bitmap.MakeTransparent()

Bitmap b = new Bitmap(ImageWithNonTransparentBackGround);
b.MakeTransparent(Color.Trasparent);

var image = new Bitmap(135, 135, PixelFormat.Format32bppArgb);
using (var g = Graphics.FromImage(image)) {
g.Clear(Color.Transparent);
g.DrawLine(Pens.Red, 0, 0, 135, 135);
}