Typeof C# example

C# > Keywords > typeof

Obtains the System.Type object for a type.

Example:

Type type = typeof(T);

• How to get the type of T from a generic List
• Reflection Example

SerialPort Class Example

C# > IO  > Ports > SerialPort

SerialPort controls a serial port file resource. 

Example

1. Gets all serial port names for the current computer.

List<String> serialPorts = new List<String>();

foreach (String portName in System.IO.Ports.SerialPort.GetPortNames())

{

  serialPorts.Add(portName);

}

System.IO.Ports Namespace C#

C# > IO  > Ports

System.IO.Ports contains classes for controlling serial port.

• SerialPort

CAST SQL Server Example

SQL Server > Built-in Functions > CAST

CAST converts an expression of one data type to another.

CAST ( expression AS data_type )

Examples

• String to number
• Number to date
• Date only - no time

ROWCOUNT SQL Server Example

SQL Server > Built-In Functions > @@ROWCOUNT

Returns the number of rows affected by the last statement.

Example:

UPDATE Person
SET Age = 31
WHERE Id = 1
IF @@ROWCOUNT = 0
    PRINT 'No rows were updated';

Public keyword C# Example

C# > Keywords > public

Public is the most permissive access level. 

It is no restrictions on accessing public members.






Example

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace WindowsFormsApplication12

{

    public partial class Form1 : Form

    {

        public class Person

        {

            public string Name;

            public int Age;

        }

        public Form1()

        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            Person p = new Person();

            p.Name = "John";

            p.Age = 35;

        }

    }

}

C# > Types > Enum > String Enum

Implement Strings Enum in C#

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 EnumString

{

    public partial class Form1 : Form

    {

        public enum Cars

        {

            [Description("Audi")] Audi,   

            [Description("Bmw")] Bmw,   

            [Description("Land Rover")] LandRover

        }

        public static string GetCarDescription(Enum car)

        {

            FieldInfo fi = car.GetType().GetField(car.ToString());

            DescriptionAttribute[] da = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);

            if (da != null && da.Length > 0)       

                return da[0].Description;

            else      

                return da.ToString();

        }

        public static IEnumerable EnumToList()

        {   

            Type type = typeof(T);   

            Array vals = Enum.GetValues(type);   

            List valList = new List(vals.Length);   

            foreach (int val in vals)   

            {

                valList.Add((T)Enum.Parse(type, val.ToString()));   

            }

            return valList;

        }

        public Form1()

        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            foreach (Cars car in EnumToList<Cars>())

            {

                comboBox1.Items.Add(GetCarDescription(car));

            }

        }

    }

}