This is a very simple text for C#.  Remember it is just a summary.


Table of Contents

  1. Start with C#
  2. TextBox, Button
  3. Comments
  4. Type
  5. if, else if, else
  6. for, while, switch
  7. a++ and ++a
  8. Method
  9. Overload
  10. Shadow
  11. Array
  12. Called by Value and Called by Reference
  13. foreach
  14. this, Indexer, operator
  15. Recursive
  16. class
  17. Inheritance
  18. base
  19. public, protected, private
  20. Polymorphism
  21. delegate
  22. try, catch, finally
  23. Library
  24. Graphics
  25. File, Directory, Two Forms
  26. ArrayList and Excel
  27. WebApplication
  28. WebService
  29. Using Mac Number
  30. PDF in Forms

Start with C#

                  Machine Language 

                           0011 1001 1101

                  Assembly Language  

                           Mor R1,M27

                           Add R1,R2,R3

                 High Level Language

                          C, C++, Java, Fortran, Cobol, Lisp, Pascal, Haskell, Perl, ...., C#

               statement         z = Math.Sin(x*y)+37;

               iteration           for, while, ..

               recursion         if (n==0) return 1;

                                     else return n*Fac(n-1);

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.IO;

namespace CompPhysics
{
     /// <summary>
     /// Form1.cs is written in resulting from the lecture "Physics using Computer".
     /// </summary>
    public class Form1 : System.Windows.Forms.Form
   {
         private System.Windows.Forms.TextBox textBox1;
         private System.Windows.Forms.Button button1;
         private System.Windows.Forms.TextBox textBox2;
         /// <summary>
         /// textBox1 is input, button1 is to run, and textBox2 is output.
         /// </summary>
         private System.ComponentModel.Container components = null;

         public Form1()
        {
              InitializeComponent();
        }

        /// <summary>
        /// We have only a Form1.
        /// </summary>
        protected override void Dispose( bool disposing )
       {
              if( disposing )
             {
                   if (components != null)
                   {
                         components.Dispose();
                   }
             }
             base.Dispose( disposing );
       }

       #region Windows Form Designer generated code
       /// <summary>
       /// InitializeComponent is generated automatically.
       /// </summary>
       private void InitializeComponent()
      {
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.button1 = new System.Windows.Forms.Button();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            //
            // textBox1
            //
            this.textBox1.Location = new System.Drawing.Point(16, 128);
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(128, 20);
            this.textBox1.TabIndex = 0;
            this.textBox1.Text = "";
            //
            // button1
            //
            this.button1.Location = new System.Drawing.Point(240, 72);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(112, 40);
            this.button1.TabIndex = 1;
            this.button1.Text = "Click to Run";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            //
            // textBox2
            //
            this.textBox2.Location = new System.Drawing.Point(32, 160);
            this.textBox2.Multiline = true;
            this.textBox2.Name = "textBox2";
            this.textBox2.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
            this.textBox2.Size = new System.Drawing.Size(408, 184);
            this.textBox2.TabIndex = 2;
            this.textBox2.Text = "output";
            //
            // Form1
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(488, 366);
            this.Controls.AddRange(new System.Windows.Forms.Control[] {
                     this.textBox2,
                     this.button1,
                     this.textBox1});
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);
       }
       #endregion

       /// <summary>
       /// Change only the part of button1_Click.
       /// </summary>
       [STAThread]
       static void Main()
       {
              Application.Run(new Form1());
        }
        private void button1_Click(object sender, System.EventArgs e)
       {

       }
    }
}

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TextBox, Button

TextBox is one of classes in .NET framework. We use two TextBox objects. One of them is for input and the other is for output. When we try to see results, we simply click Button objects. Also Button is one of classes in .NET framework. Each component has a property, which contains Back Ground Color, etc. When you make a textbox or a button, you can use Tool Box, which you can find in the left part of Visual Studio .NET IDE.

                 this.textBox1.Text = "Yahoo!";

                 this.textBox2.Text = this.textBox1.Text;

                - Graphical User Interface (GUI)

                - Console Application

using System;

namespace HelloWorld
{
     class Hello
     {
           public Hello( )
          {
          }
     }
}

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Comments

            /* This is the answer to the question.

              there are many lines in codes

              So we use as */

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Type

Code:

          int x; // first integer

          int y; // second integer  

          int z; // third integer      // This three statements become a single as  int x,y,z;

          .....

          x = 7; // x variable, 7 value

          .....

          x=y+10;

          .....

          x="Hello" // It makes an error, because x is an integer.

          x=x - 1; // Good Expression.

               x+y*z; // the same as math x+yz

          x+(y*z); // this is different from (x+y)*z  

                   "abc", "good bye \n", "abc\tdef", "abc"+"def"="abcdef",...

Code:

          double i = 1.0;
          double k = 8.0;
          k = Convert.ToDouble(textBox1.Text);
          double j = i+k;
          int i1 = 5, k1= 3;
          int j1 = i1%k1;
          bool tf = false;
          string str = "this is a string.";
          if(tf) textBox2.Text = Convert.ToString(tf);
          else textBox2.Text = "false";
          textBox2.Text += "\r\n";
          textBox2.Text += str+"\r\n";

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if, else if, else

- Problem

                specified informally or formally ( i.e. mathematically)

- Algorithm

                abstract solution to a problem, expressed formally or informally.

               Mathematics - formal

               English - informal

               pseudo-code

- Program

               concrete solution to a problem, i.e. a concrete instantiation of an algorithm.

                   2. There may be more than one program to realize a given algorithm.

            get ten numbers

            add numbers all together

            divide sum by ten

- if

- if / else

- switch

- while

- do / while

- for

- foreach

bool foo = false;
bool foo2 = true;
if(foo)
{
        textBox2.Text += "if is running"+"\r\n";
        textBox2.Text += "\t more";
}
else if(foo2)
{
        textBox2.Text +="foo2 is true";
}
else
{
        textBox2.Text += " foo is false";
}
textBox2.Text += " the end";

 

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for, while, switch

                  217.345e5       float - 32 bit,   double - 64 bit

                  conversion         x = (float) n / (float) y;

                 1byte = 8 bit , ASCII = 7 bit, Unicode = 16 bit, MIME = 6 bit

                To terminate running code, control <cmd>.

// for
int sum = 0;
for(int a = 10; a >= 0; a -= 2)
{
       textBox2.Text += Convert.ToString(a)+"\r\n";
       sum += a; // sum = sum + a;
}
// while
int k = 0;
while(k < 10)
{
       textBox2.Text +="kkkk"+"\r\n";
       k++;
}
// switch
string k = textBox1.Text;
switch(k)
{
      case "yes":
      case "YES":
      case "Yes":
          textBox2.Text = " k is yes";
      break;
      case "no":
          textBox2.Text = " k is no";
      break;
      default:
          textBox2.Text = " k is not 1 nor 2";
      break;
}

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a++ and ++a

               x = x+1;     x+= 1;     x++;       ++x;

               x = x+7;     x+=7;

              +=            -=           /=      *=        %=

             x=2;     y=x++ + 7;  => y=9 and x=3; "after add".

             x=2;     y=++x + 7;  => y=10 and x=3; "before add".

// ++a, a++;
int a = 10;
a++;
++a;
int b = a + 1;
a++;
textBox2.Text += " b is "+Convert.ToString(b);

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Method

Examples: Console.WriteLine()

                Console.ReadLine()

                Int32.Parse()

                MessageBox.Show()

Syntex: <class name>.<method name> for static method.

<object name>.<method name> for dynamic method.

using System;    => We do not need to write a long commend as System.Console.WriteLine();

Method call or invocation:

Syntex: <method name>(<argument list>)

ex) Int32.Parse("123"); 

Method definition:

Syntex: <return type> <method name>(<parameter list>) { <body>}

Example:

Method Code:
private void button1_Click(object sender, System.EventArgs e)
{
        double c = -100.0;
        a = Convert.ToInt32(textBox1.Text);
        textBox2.Text = Convert.ToString(c);
        c = Square(5.2);
        textBox2.Text +=" "+ Convert.ToString(c);
}

int a;
int c; // think about shadow
private void Square()
{
       c = a*a;
}

Another Example:

char[] c;
private void button1_Click(object sender, System.EventArgs e)
{
      c = textBox1.Text.ToCharArray();
      textBox2.Text = Convert.ToString(c[3]);
}

 

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overload

We can use the same names for Method with different input types.

private int Square(int a)
{
        return a*a;
}


private double Square(double a)
{
        return a*a;
}

private int Square(double a)   // it can not be distinguished by double Square(double a), thus, it makes an error. The type of return is irrelevant.
{
        return a*a;
}

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Shadow

To make a method to be an independent code, the rule of shadow is adopted.

int a = 10;
public int ShadowTest(int x)
{
        int a = 23;
        return a;
}

As we can see in the above code, the return value will be 23.

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Array

Data Structure:

        structured value (or objects)

        whose components are other values (or data structures)

Examples:  Lists, Trees, Pairs, Tuples, Stacks, Queues, ... and Arrays.

Array: Fixed-sized set of continuous memory locations.

n elements

0      First
1 Second
2 Third
3 Fourth
 
 
 
n-1 n-th

Data structures are characterized by three kinds of operations on them.

a.Length => length (size) of a

Code:

// Array
int[] a = new int[6];
a[0] = 8;
a[1] = 2;
a[2] = 6;
a[3] = a[0] + a[2];
a[4] = 7;
a[5] = 6;

// Multiple Array

double[,,] a = new double[2,3,2]; // first 0,1 second 0,1,2, third 0,1
a[1,1,0] = 10.678;
a[1,2,1] = 12.9;
textBox2.Text = Convert.ToString(a[1,1,1]);
 

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Called by Value and Called by Reference

Called by Value: Make copy of argument before passing ( int, float, bool, char, double) to method.

Called by Reference: A reference to value is passed to method. (arrays, objects, strings,...).

If arrays were immutable, no difference between CBV and CBR (except in efficiency).

If arrays are mutable, results can be different.

As pointer in C, the keywork "ref" is used in C#.

Code:
private void button1_Click(object sender, System.EventArgs e)
{
        a[0] = 2.0;
        Replace(a);
        b = 4.0;
        Replace(b);
        textBox2.Text = Convert.ToString(b);
}

double[] a = new double[2];
double b;
private void Replace(double[] c)
{
       c[0] = 5.0;
}
private void Replace(double c)
{
       c = 5.0;
}

When a method is executed, all local variables are disappeared except return variables or global variables.

private void button1_Click(object sender, System.EventArgs e)

{

ff(x);

textBox1.Text += x[0] + "\r\n";

textBox1.Text += x[1] + "\r\n";

}

double[] x = { 1.5, 2.9 };

private void ff(double[] x)

{

double[] xx;

double[] y = { 2.4, 1.6 };

xx = y;   // compare x = y;

x[1] = xx[1];

}

 

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foreach

foreach is useful when we do not know the exact Length of array.

Of course, it is possible to change foreach to for.

Code:
private void button1_Click(object sender, System.EventArgs e)
{
    // Student[] y;
    double[,,] x = new double[2,4,3];
    x[0,0,0] = 2.8;
    x[0,1,0] = 1.1;

    foreach(double k in x)
    {
        textBox2.Text += Convert.ToString(k)+"\r\n";
    }
 // for(int i =0; i<2; i++)
 // for(int j =0; j<4; j++)
 // textBox2.Text += Convert.ToString(x[i,j])+"\r\n";
}

 

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this, Indexer, operator, static

In order to distinguish variables inside class and the same name variables inside a method,

we use the keywork "this". In consequence, this is used to overcome shadow.

Code:

private int x = 1;
// private int y = x;

private void button1_Click(object sender, System.EventArgs e)
{
    int x = 7;
    int y = this.x;
    textBox2.Text = Convert.ToString(y);
}

To access private members which have index, we use indexer using the keyword "this".

Code:

private double[,] el;
public double this[int a, int b]
{
    get{return el[a,b];}
    set{el[a,b]=value;}
}

It is useful to use keyword operator to see our usual operator.

Code:

public static Matrix operator *(Matrix a, Matrix b)  // This code must locate at Matrix.
{
      Matrix b = new Matrix();
      b.SetSize(a.SizeOfRow,c.SizeOfColumn);
      double
sum;
      for
(int k = 0; k < b.SizeOfRow; k++) {
             for
(int j = 0; j < b.SizeOfColumn; j++) {              
                         sum = 0.0;
       
                         for
(int s = 0; s < a.SizeOfColumn; s++)   sum += a.Element[k,s]*c.Element[s,j];

                            b.Set(k,j,sum);

                 }

       }

     return b;
}
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Recursive

"To iterate is human, to re-curse is divine."

Example: Factorial    n! = n*(n-1)*(n-2)....(2)(1)

fac(n)    =   1                        if n=0
 n*fac(n-1)         if n > 0

Code for Recursive:
private void button1_Click(object sender, System.EventArgs e)
{
            int a = Convert.ToInt32(textBox1.Text);
            textBox2.Text = Convert.ToString(Factorial(a));
}
private int Factorial(int n)
{
            if( n == 0) return 1;          
            else return n*Factorial(n-1);   // or: return (n <= 1) ? 1 : n*Factorial(n-1);
}

 

Example 2:

private int Fib(int n)

{

          if(n=0) return 0;

         else if (n=1) return 1;

         else return Fib(n-1)+Fib(n-2);

}

Example 3:

private int GCD(int x, int y)

{

    if(x==y) return x;

    else return GCD(y,x%y);

}

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class

A class is a template for an object.

An object encapsulates states and methods.

class is used to achieve ADT (Abstract Data Type).
 

Code:

private void button1_Click(object sender, System.EventArgs e)
{
    Student a = new Student("chung");
    Student b = new Student("kim",345);
    b.Number = 346;
    textBox2.Text = b.Name+" "+Convert.ToString(b.NumberAdd(20));
}
public class Student
{
    private string n; // private objects
    private int num; // private objects
    public Student() // Constructor
    {
        n = "ftfttt";
        num = 0;
    }
    public Student(string name) // overload Constructor
    {
        n = name;
        num = 0;
    }
    public Student(string name, int a) // Constructor
    {
        n = name;
        num = a;
    }
    public string Name // Property
    {
        get{return n;}
    }
    public int Number // Property
    {
        get{return num;}
        set{num=value;}
    }
    public int NumberAdd(int a) // public Method
    {
        return PrivateNumberAdd(a);
    }
    private int PrivateNumberAdd(int a) // private Method
    {
        num = num + 2*a;
        return num;
    }
}  // end of class

Another code:

public class Coin

{

     private int val;

     private string state = "Head"; // private object

     public Coin()

    {

    }

    public Coin(int price) // constructor

    {

        val = price;

    }

    public int Value // property

    {

        get{return val;}

        set{val=value;}

    }

    public string State // property

    {

        get{return state;}

    }

    private bool front = true;

    public void Flip() // method

    {

        if(front) {state = "Tail";front=false;}

        else {state = "Head";front=true;}

    }

}

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Inheritance

To reuse classes, we have to consider inheritance.

As an example for inheritance, we consider three classes.

Point
   |
Circle
   |
Cylinder
 

Code:

private void button1_Click(object sender, System.EventArgs e)
{
    Cylinder cy = new Cylinder(2.3,5.6,1.0,1.0);
    cy.h = 2.0;
    Circle c = new Circle(2.1,4.5,6.7);
    Cylinder cy1 = new Cylinder(2.3,5.6,1.0,3.0);
    textBox2.Text = Convert.ToString(cy1.Volume());

// Circle cir = new Circle(2.3,5.6,1.0,1.0);

// cir = new Cylinder(2.3,2.3,1.0,4.3);

// textBox2.Text = Convert.ToString(cir.Area());
}   // Main Code

public class Point
{
    protected double x, y;
    public Point()   // Constructor
    {
        x = 0.0;
        y = 0.0;
    }
    public Point(double a, double b)  // Constructor Overloading
    {
        x = a;
        y = b;
    }
    public double X
    {
        get{return x;}
    }
    public double Y
    {
        get{return y;}
    }
}
public class Circle : Point  // Circle is inherited from Point
{
    protected double r;
    public Circle() : base()
    {
    }
    public Circle(double a, double b, double c) : base(a,b)
    {
        r = c;
    }
/*  public Circle(double a, double b, double c)
    {
        x = a;
        y = b;
        r = c;
    }  */
    public virtual double Area()
    {
        return r*r*Math.PI;
    }
}
public class Cylinder : Circle
{
    public double h;
    public Cylinder(double a, double b, double c, double d) : base(a,b,c)
    {
        h = d;
    }
    public override double Area()
    {

        return base.Area()*2.0+h*2.0*Math.PI*r;
    }
    public double Volume()
    {
        return r*r*Math.PI*h;
    }
}

 

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base

When we make derived classes, we use keyword "base" to avoid duplication of making constructors.

Code:

public ClassConstructor(int a, int b, int c) : base(a, b)

{

       k = c;

}

public void Method2(int x)

{

      base.Method1(x);

}

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protected, public, private

"public" methods can be called outside class, while "private" methods or variables can be called only inside the corresponding class.

"protected" methods or variables can be called in derived classes.

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polymorphism

Shapes

   |           \

 2D         3D

   |

Rectangular

   |

Square

When we make all classes, we write new Shape(..) however this Constructor has no sense.

We use keyword abstract - override or virtual - override. It is not needed to override for virtual.

If at least one abstract is used in a class, then the class is abstract.

Code:
public abstract class Point
{
    protected double x, y;
    public Point()
    {
        x = 0.0;
        y = 0.0;
    }
    public Point(double a, double b)
    {
        x = a;
        y = b;
    }
    public double X
    {
        get{return x;}
    }
    public double Y
    {
        get{return y;}
    }
    public abstract int Meth();
   {
        return 3;
   }
}
public class Circle : Point
{
    protected double r;   
    public Circle() : base()
    {
    }
// public Circle(double a, double b, double c) : base(a,b)
// {
// r = c;
// }
    public Circle(double a, double b, double c)
    {
        x = a;
        y = b;
        r = c;
    }
    public double Area()
    {
        return r*r*Math.PI;
    }
    public override int Meth()
    {
        return 4;
    }
}
public class Cylinder : Circle
{
    public double h;
    public Cylinder(double a, double b, double c, double d) : base(a,b,c)
    {
        h = d;
    }
    public new double Area()
    {
        return r*r*Math.PI*2.0+h*2.0*Math.PI*r;
    }
    public double Volume()
    {
        return r*r*Math.PI*h;
}
// public override int Meth()
// {
//     return 5;
// }
}

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delegate

When a programmer wants to use a method as an argument in a method, he have to use "delegate".

For example, EventHandler is a delegate name.

Code:

private void button1_Click(object sender, System.EventArgs e)
{
    D4 kk = new D4(Mul);  // D4 is delegate name, and method "Mul" is delivered.
    textBox2.Text = All(kk,-12.3,10.1);
}  // Main

private double Add(double a, double b)
{
    return a+b;
}
private double Sub(double a, double b)
{
    return a-b;
}
private double Mul(double a, double b)
{
    return a*b;
}
private double Div(double a, double b)
{
    return a/b;
}
private string All(D4 ss, double a, double b)
{
    if(ss(a,b)>0.0) return "bigger than zero";
    else return "small";
}
private delegate double D4(double a, double b);

 

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try, catch, finally

Exception handling: Programmer can control errors, with which we meet anomalous situations that

the program can recover from

Code with try-catch-finally:
private void button1_Click(object sender, System.EventArgs e)
{
    double a;
    try
    {
        a = Convert.ToDouble(textBox1.Text);
    }
    catch(FormatException errrr)
    {
        MessageBox.Show(errrr.Message,"you gave nothing.",MessageBoxButtons.OK, MessageBoxIcon.Error);
        a = 1.0;
    }
    catch(IndexOutOfRangeException)
    {
        a = 3.0;
    }
    finally
    {
        a =5.0;
    }
    double b = 10.0/a;
    textBox2.Text = Convert.ToString(b);
}

user-defined exception

//C#: Exception Handling: User defined exceptions
//Author: rajeshvs

using System;
class MyException : Exception
{
            public MyException(string str)
            {
                        Console.WriteLine("User defined exception");
            }
}
class MyClient
{
            public static void Main()
            {
                        try
                        {
                                    throw new MyException("RAJESH");
                        }
                        catch(Exception e)
                        {
                                    Console.WriteLine("Exception caught here" + e.ToString());
                        }
                        Console.WriteLine("LAST STATEMENT");
            }
}

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Library

In order to use Numerical Recipes as a library, we download NumericalRecipes.zip
from internet. and unzip in an appropriate directory,
for example, /Visual Studio Projects/NumericalRecipes.

When we make an WindowsApplication1 (which is default) project,
we can see a Form1.cs in the WindowsApplication1 project under the
WindowsApplication1 solution.

Put our mouse at the solution name, and click the right button of
mouse, then we can see some menu. Find the item of Add and add the
project of NumericalRecipes. Then we can see two projects: one is
our project, and the other is NumericalRecipes. Now what we have to
do is that we allow the original project to notice the library (the
second project). In our project, we should find Reference. Put
mouse on Reference, click the right button, and add the project of
NumericalRecipes. It is convenient to use "using
NR=NumericalRecipes;" in the file of Form1.cs of our original project.

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Graphics

C# is useful to create graphics.

Usual coordinate system measured in pixels.

(0,0)-------x--------(maxX,0)
|                  |                    |

|                  |                    |

y---------(x,y)                 |

|                                       |

(0,maxY)------------(maxX,maxY)

Graphics object allows one access to a graphics context.

To access or create a graphic object

Colors: ARGB(alpha-red-green-blue), alpha means transparency.

All represented by bytes: 0-255.

We can use names of color: Color.Red, Color.Green, Color.Blue, Color.Yellow, Color.Pink.

Brushes and Pens: See below codes.

Shapes: DrawLine(pen1, x1,y1,x2,y2); FillRectangle(brush1,x1,y1,width,height);

Graphics Transforms; g.TranslateTransform(a,b); x -> x+a, y->y+b      g.RotateTransform(a)

Code:

Graphics g;
private void button1_Click(object sender, System.EventArgs e)
{
    g = panel1.CreateGraphics();
    // Color c = Color.FromArgb(255,255,0,0);
    ColorDialog c = new ColorDialog();
    c.FullOpen = true;
    DialogResult re = c.ShowDialog();
    SolidBrush b = new SolidBrush(c.Color);
    // g.FillEllipse(b,0,0,100,135);
    Pen p = new Pen(b,2);
    // g.DrawEllipse(p,2,34,200,226);
    double v0 = Convert.ToDouble(textBox1.Text);
    PointF[] po = new PointF[100];
    for(int time = 0; time < po.Length ; time++)
    po[time] = new PointF((float)(v0*time),(float)(150.0+100.0*Math.Sin(0.2*time)));
    g.DrawLines(p, po);
}
private void button2_Click(object sender, System.EventArgs e)
{
    g.Clear(panel1.BackColor);
}

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File, Directory, Two Forms

There are nice two classes named as File and Directory. They are useful to write data into hard disc.
Or we can use StreamWriter.

Code:

private void button1_Click(object sender, System.EventArgs e)

{
    string s = textBox2.Text;
    SaveFileDialog file = new SaveFileDialog();
    DialogResult res = file.ShowDialog();
    file.CheckFileExists = false;
    string filename = file.FileName;
    StreamWriter wr = new StreamWriter(filename);
    wr.WriteLine(s);
    wr.Close();

}
 

Two Forms

private void button1_Click(object sender, System.EventArgs e)

{

    textBox1.Text="i will see";

    Form2 form2 = new Form2();

    form2.Show();

}      // Form1 method

 

private void button1_Click(object sender, System.EventArgs e)

{

    textBox1.Text = "second form works";

}

private void button2_Click(object sender, System.EventArgs e)

{

    this.Dispose();

}   // Form2 method

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ArrayList and Excel

Extensible Array: ArrayList al = new ArrayList(1);

We can add arbitrary number of lists.
 

Code:

private void button1_Click(object sender, System.EventArgs e)

{

    ArrayList x = new ArrayList(1);
    int ix = 10;
    double y = 234.999;
    string z = "yyyyy";
    x.Add(ix);
    x.Add(345.876);
    x.Add(y);
    x.Add("ssss");
    x.Add(z);

    x.Insert(2,"in front of y=234.999");
    x.Remove(y);
    x.RemoveAt(0);

    for(int i =0; i< x.Count; i++)
    textBox2.Text += Convert.ToString(x[i])+"\r\n";

    x.Clear();

}

One of the best way in handling data would be using Excel.

In order to use Excel, we first have to install Microsoft.Office.Interop.Excel.dll by executing oxppia.zip

into ProgramFiles/.NETFramework/Microsoft.Net.

You can find the dll library using the keyword "Primary Interoperator Assemblers" in google.

After we add it as a reference, we can run the following code.

using System;

using System.Reflection; // In order to handle Type.Missing

using Xls = Microsoft.Office.Interop.Excel;

namespace Science.Mathematics.Graphics

{

/// <summary>

/// Excel

/// </summary>

public class Excel

{

public Excel()

{

}

private string bookname="Book1", sheetname="Sheet1",

cell="A1", cellend="B2";

public string NameOfBook

{

get{return bookname;}

set{bookname = value;}

}

public string NameOfSheet

{

get{return sheetname;}

set{sheetname = value;}

}

public string StartingCell

{

get{return cell;}

set{cell = value;}

}

public string EndingCell

{

get{return cellend;}

set{cellend = value;}

}

public void Write(double[,] obj)

{

Xls.Application objApp = new Xls.Application();

Xls.Workbooks objBooks = objApp.Workbooks;

Xls.Workbook objBook = objApp.Workbooks.Open

(System.Windows.Forms.Application.StartupPath + "\\"+bookname+".xls",

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing);

Xls.Sheets objSheets = objBook.Worksheets;

int findsheet = 0;

Xls.Worksheet objSheet;

for(int k = 0; k < objSheets.Count; k++)

{

objSheet = (Xls.Worksheet)objSheets.get_Item(k+1);

if(objSheet.Name == sheetname) findsheet = k+1;

}

if(findsheet==0)

{

objSheet = (Xls.Worksheet)objSheets.Add( Missing.Value,Missing.Value,

Missing.Value, Missing.Value);

objSheet.Name = sheetname;

}

else objSheet = (Xls.Worksheet)objSheets.get_Item(findsheet);

Xls.Range range;

range = objSheet.get_Range(cell, Missing.Value);

range = range.get_Resize(obj.GetLength(0),obj.GetLength(1));

range.set_Value(Missing.Value, obj);

objBook.Save();

// objApp.Visible = true;

// objApp.UserControl = true;

objApp.Quit();

}

private int row, column;

public int NumberOfRow

{

get{return row;}

}

public int NumberOfColumn

{

get{return column;}

}

public void FindSize()

{

Xls.Application objApp = new Xls.Application();

Xls.Workbooks objBooks = objApp.Workbooks;

Xls.Workbook objBook = objApp.Workbooks.Open

(System.Windows.Forms.Application.StartupPath + "\\"+bookname+".xls",

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing);

Xls.Sheets objSheets = objBook.Worksheets;

int findsheet = 0;

Xls.Worksheet objSheet;

for(int k = 0; k < objSheets.Count; k++)

{

objSheet = (Xls.Worksheet)objSheets.get_Item(k+1);

if(objSheet.Name == sheetname) findsheet = k+1;

}

objSheet = (Xls.Worksheet)objSheets.get_Item(findsheet);

Xls.Range range = objSheet.get_Range(cell,cellend);

Object[,] x = (Object[,])range.get_Value( Missing.Value );

row = x.GetLength(0);

column = x.GetLength(1);

objApp.Quit();

}

public void Read(double[,] y)

{

Xls.Application objApp = new Xls.Application();

Xls.Workbooks objBooks = objApp.Workbooks;

Xls.Workbook objBook = objApp.Workbooks.Open

(System.Windows.Forms.Application.StartupPath + "\\"+bookname+".xls",

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing,

Type.Missing,Type.Missing,Type.Missing,Type.Missing);

Xls.Sheets objSheets = objBook.Worksheets;

int findsheet = 0;

Xls.Worksheet objSheet;

for(int k = 0; k < objSheets.Count; k++)

{

objSheet = (Xls.Worksheet)objSheets.get_Item(k+1);

if(objSheet.Name == sheetname) findsheet = k+1;

}

objSheet = (Xls.Worksheet)objSheets.get_Item(findsheet);

Xls.Range range = objSheet.get_Range(cell,cellend);

Object[,] x = (Object[,])range.get_Value( Missing.Value );

for(int i = 0; i<y.GetLength(0); i++)

for(int j = 0; j<y.GetLength(1); j++)

y[i,j] = Convert.ToDouble(x[i+1,j+1]);

// objApp.Visible = true;

// objApp.UserControl = true;

objApp.Quit();

}

}

}

And then, use the tool for graph, Origin.

using System;

namespace Science.Mathematics.Graphics

{

        /// <summary>

       /// Origin

       /// </summary>

       public class Origin

      {

                 public Origin()

                {

                }

                private string name;

                public string NameOfFile

               {

                          get{return name;}

                          set{name=value;}

               }

               public void Run()

              {

                        System.Diagnostics.Process Proc = new System.Diagnostics.Process();

                        Proc.StartInfo.WorkingDirectory = System.Windows.Forms.Application.StartupPath;

                        Proc.StartInfo.FileName = name+".opj";

                        Proc.Start();

              }

       }

}

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WebApplication

There are several project types such as ConsoleApplication, WindowsApplication, WebApplication, and WebService.

The following code is one of WebApplication where we use WebService also.

Code:
private localhost.Service1 ws = new localhost.Service1();
private void Button1_Click(object sender, System.EventArgs e)
{
    TextBox2.Text =
    Convert.ToString(ws.Fac(Convert.ToInt32(TextBox1.Text)));
}

 

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WebService

WebService will be one of powerful tools in the future of computing. Be aware of the power of WebService. The following code is a part of a project of WebService.

Code:

[WebMethod]
public string HelloWorld()
{
    return "Hello World";
}
[WebMethod]
public int Fac(int x)
{
    if(x == 0) return 1;
    else return x*Fac(x-1);
}

 

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Using Mac Number

It is possible to make a windows application which runs in a specific computer only. To do so, we have to use Mac number which is an identification for each computer.

Code:

using System;

using System.Management;

namespace EngineLibrary

{

/// <summary>

/// MACAddress

/// </summary>

public class WhoAmI

{

private string given="000802DE1CD4"; //"0004764BDFEF";  // Typical Mac Number

public WhoAmI()

{

}

private string address;

public string MACAddress

{

get{return address;}

}

private bool same;

public bool Same

{

get{return same;}

}

public void Find()

{

ManagementClass mC = new ManagementClass("Win32_NetworkAdapterConfiguration");

ManagementObjectCollection mOC = mC.GetInstances();

address=String.Empty;

foreach(ManagementObject mO in mOC)

{

if(address==String.Empty)

{

if((bool)mO["IPEnabled"]==true) address=mO["MacAddress"].ToString();

}

mO.Dispose();

}

address=address.Replace(":","");

same = (address==given) ? true : false;

}

}

}

The driver code to use the class of WhoAmI is following.

Code:

using System.Windows.Forms;

................

WhoAmI iAm = new WhoAmI();

iAm.Find();

if(iAm.Same)

{

}

else

{

try{throw new Exception();}

catch (Exception)

{

MessageBox.Show("Please support our authors.",

"Invalid user",MessageBoxButtons.OK, MessageBoxIcon.Error );

}

}

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PDF in Forms

We can show a pdf file in a windows application form. It is important to refer two dll files: AxInterop.AcroPDFLib.dll, Interop.AcroPDFLib.dll which can be downloaded in the Internet.

Code:

using System;

using System.Drawing;

using System.Collections;

using System.ComponentModel;

using System.Windows.Forms;

using System.Data;

namespace ShowPDF

{

/// <summary>

/// Form1

/// </summary>

public class Form1 : System.Windows.Forms.Form

{

private AxAcroPDFLib.AxAcroPDF axAcroPDF1;

private void InitializeAdobe()

{

try

{

System.Resources.ResourceManager resources = new

System.Resources.ResourceManager(typeof(Form1));

this.axAcroPDF1 = new AxAcroPDFLib.AxAcroPDF();

((System.ComponentModel.ISupportInitialize)(this.axAcroPDF1)).BeginInit();

this.axAcroPDF1.Enabled = true;

this.axAcroPDF1.Location = new System.Drawing.Point(84,38);

this.axAcroPDF1.Name = "axPdf1";

this.axAcroPDF1.OcxState =

((System.Windows.Forms.AxHost.State)(resources.GetObject("axAcroPDF1.OcxState")));

this.axAcroPDF1.Size = new System.Drawing.Size(854,

470);

this.axAcroPDF1.TabIndex = 0;

this.Controls.Add(this.axAcroPDF1);

((System.ComponentModel.ISupportInitialize)(this.axAcroPDF1)).EndInit();

axAcroPDF1.LoadFile("../../aoki.pdf");

axAcroPDF1.Show();

}

catch (Exception ex)

{

MessageBox.Show(ex.Message);

}

}

/// <summary>

///

/// </summary>

private System.ComponentModel.Container components = null;

public Form1()

{

//

// Windows Form

//

InitializeComponent();

InitializeAdobe();

//

// TODO: InitializeComponent

//

}

/// <summary>

///

/// </summary>

protected override void Dispose( bool disposing )

{

if( disposing )

{

if (components != null)

{

components.Dispose();

}

}

base.Dispose( disposing );

}

#region Windows Form Designer generated code

/// <summary>

///

///

/// </summary>

private void InitializeComponent()

{

//

// Form1

//

this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);

this.ClientSize = new System.Drawing.Size(344, 326);

this.Name = "Form1";

this.Text = "Form1";

}

#endregion

/// <summary>

///

/// </summary>

[STAThread]

static void Main()

{

Application.Run(new Form1());

}

}

}


 

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Author: Myung-Hoon Chung,  E-mail: mhchung@hongik.ac.kr
Copyright 2007  [Myung-Hoon Chung, Hongik University]. All rights reserved.
Revised: 03/19/08.