Create new directory with DirectoryInfo C#

C# > Files > DirectoryInfo Class

Use this class for create, move and enumerating directories and subdirectories. 

Example 

Create new directory

DirectoryInfo directoryInfo = new DirectoryInfo(@"c:\Yourdir");

try

{

if (!directoryInfo.Exists)

       {

              directoryInfo.Create();

       }

}

catch (Exception ex)

{

MessageBox.Show("DirectoryInfo error: {0}", ex.ToString());

}

finally { }

Get Directory Size C#

C# > IO  > FileInfo > Length

Get the size of the file in bytes. 

Example

Get Directory Size C#

public long DirectorySize(DirectoryInfo dir)

{

       long size = 0;

       foreach (FileInfo file in dir.GetFiles())

       {

              size += file.Length;

       }

      foreach (DirectoryInfo directory in dir.GetDirectories())

       {

              size += DirectorySize(directory);

       }

       return size;

 }

DirectoryInfo dir = new DirectoryInfo(@"C:\Temp");

long size = DirectorySize(dir);

C# Capture Screen to PictureBox

C# > Drawing > Capture Screen

Bitmap printscreen = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height);

Graphics graphics = Graphics.FromImage(printscreen as Image);

graphics.CopyFromScreen(0, 0, 0, 0, printscreen.Size);

using (MemoryStream s = new MemoryStream())

{

printscreen.Save(s, System.Drawing.Imaging.ImageFormat.Bmp);

       picCapture.Size = new System.Drawing.Size(this.Width, this.Height);

       picCapture.Image = Image.FromStream(s);

}

XmlDocument C# Example

C# > XML > XmlDocument

Represents an XML document.

Example

XmlDocument doc = new XmlDocument();

doc.Load(xmlfile);

NetworkChange Class C#

C# > System.Net > NetworkInformation > NetworkChange

Use this class to receive notification when the IP address of a network interface changes.
Changes can appears when:

• disconnect network cable
• out of range of a wireless Local Area Network
• hardware failure

Events:

• NetworkAvailabilityChanged

C# NetworkInformation NameSpace

C# > System.Net > NetworkInformation

Provides access to network address information and traffic data.

Classes

• NetworkChange

ReadAllBytes C# Example

C# > Files > File Class > ReadAllBytes

Opens, reads the contents of the file into a byte array, and then closes the file.

Example

Read bytes from jpg file and display to PictureBox.

var bytes = File.ReadAllBytes("D:\\Pics\\1.jpg");

pictureBox1.Image = Image.FromStream(new System.IO.MemoryStream(bytes));

C# File Class

C# > Files > File Class

Use the File class for:

• copy, move, rename, create, open, delete to a single file at a time. 
• get and set file attributes.

All File methods are static.

Methods

• ReadAllBytes
• OpenText
• AppendText
• Move

IsNumeric equivalent in LINQ example

C# > LINQ > IsNumeric

IsNumeric equivalent in LINQ example.

double value;

var total = (from DataRow dr in dataTable.Rows

                where double.TryParse(dr["value"], out value)

                select Convert.ToDouble(dr["value"])).Sum();

Dependency Injection C# Example

C# > Patterns > Dependency Injection 

Dependency injection promotes loose coupling of components by passing dependencies to an object rather than having an object instantiate its own dependencies.(http://www.blackwasp.co.uk/DependencyInjection.aspx)

• Autofac
• Autofac modules

       

Example

        public interface ITruck

        {

            void Go(double distance);

        }

        public class Truck : ITruck

        {

            public double Consumption{ get; set; }

            public void Go(double distance)

            {

                double necessary_fuel = Consumption * distance;

            }

        }

        public interface IRoute

        {

            void AddTruck(ITruck dependency);

        }

        public class Route : IRoute

        {

            ITruck _truck;

            public double Distance { get; set; }

            public void AddTruck(ITruck truck)

            {

                _truck = truck;

            }

            public void TruckGo()

            {

                _truck.Go(Distance);

            }

        }

            Route route = new Route();

            route.Distance = 100;

            Truck truck = new Truck();

            truck.Consumption = 20;

           

            route.AddTruck(truck);

            route.TruckGo();

C# System.Security AccessControl

C# > System.Security > AccessControl

With AccessControl you can control, access and audit security related actions on securable objects.

• AuthorizationRuleCollection 

C# > System.Security

C# > System.Security

• NET Framework security system
• provide access to authentication
• provide crytographic services
• control access to operations based on policy
• rights management of application-created content

Classes

• AccessControl

Dynamic Type C# Example

C# > Types > dynamic

The dynamic enables bypass compile-time type checking. These operations are resolved at run time. 

Example

dynamic dyn = 1;

object obj = 1;

var dyn_type = dyn.GetType(); // System.Int32

var obj_type = obj.GetType(); // System.Int32

dyn = dyn + 1; //Ok

obj = obj + 1; // Error    1      Operator '+' cannot be applied to operands of type 'object' and 'int'

Object Type C# Example

C# > Types > object

 You can assign values of any type to variables of type object. 

Example

object obj;

obj = 1; 

string type =  obj.GetType().Name; //Int32

   

obj = "string";

type = obj.GetType().Name; //String

Dns Get Host By Name C# Example

C# > System.Net > Dns

Retrieves information about a specific host from the Internet Domain Name System (DNS).

Example

  IPHostEntry hostInfo = Dns.GetHostByName("www.microsoft.com");

  string hostName = hostInfo.HostName;

  IPAddress[] addressList = hostInfo.AddressList;

  foreach (IPAddress ipAddress in addressList)

  {

              

  }

C# System.Net

C# > System.Net

Provides  programming interface for:

• network protocols
• cache policies
• e-mail
• network traffic data and network address information
• networking functionality

Classes:

• Dns

Namespaces

• NetworkInformation

Assembly Class C# Example

C# > System > Reflection > Assembly

Assembly class:

• load assemblies
• explore the metadata 
• find the types contained in assemblies and to create instances of those types.

Example

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Reflection;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace WindowsFormsApplication27

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            Assembly a = typeof(Form1).Assembly;

            MessageBox.Show(a.FullName);

        }

    }

}

Reflection C#

C# > System > Reflection

Reflection provides objects that encapsulate assemblies, modules and types.
With reflection you can read metadata for finding assemblies, modules and types information at runtime. 
These objects also can be used to manipulate instances of loaded types.

• Asembly class

Func C# Example

C# > System > Func

Func is a parameterized type. 

• accepts any number and kinds of input parameters
• one type of the return value T
• stores anonymous methods 

Example

1. Func<T, TResult>

Func<int, int> power = p => p * p;

int[] numbers = { 1, 2, 3 };

IEnumerable<int> powers = numbers.Select(power);

foreach (int p in powers)

     Console.WriteLine(p);