C#

Software_Specialist wrote:

Is it possible to create an instance of a class under one button and use it in another button.

Software_Specialist wrote:

So is there any way to do so. I dont think its a good idea to create instance of a class globally because whole thing is that i want to make use of register button n so on.

Software_Specialist wrote:

how to store it as field

public class MyForm : Form
{
    // This is the field. It is "private" (cannot be seen outside this instance
    // of the class. It is of type "MyObject" (You'll want to put your own class
    // name in here). And it is called "someObject" (so you can refer to it in
    // other code in the class.)
    private MyObject someObject;
...
    // This could be the register button handler (for example)
    public void TheRegisterMethod()
    {
        this.someObject = new SomeObject("blah");
    }
...
    // This could be a button handler method
    public void SomeOtherMethodThatNeedsSomeObject()
    {
        this.SomeObject.DoStuff();
    }
}

class MyClass
{        
public int MyInt1;        
public int MyInt2;        
public int MyInt3;  
private int[] tmparray;      

public int[] MyIntArray        
{                
get                
{                        
tmparray = new int[3];                        
tmparray[0] = MyInt1;                        
tmparray[1] = MyInt2;                        
tmparray[2] = MyInt3;                        
return tmparray;                
}                
set                
{                        
MyInt1 = value[0];                        
MyInt2 = value[1];                        
MyInt3 = value[2];                
}        
}        
public MyClass()        
{                
MyIntArray = new int[3];        
}
}

class MyBaseClass
    {
        public int[] MyIntArray
        {
            get
            {
                //.. Some functionality
            }
            set
            {
                //.. some functionality
            }
        }

        public MyBaseClass()
        {
            MyIntArray = new int[3];
        }
    }

    class MyClass : MyBaseClass
    {
        public int MyInt1;
        public int MyInt2;
        public int MyInt3;
        private int[] tmparray;

        public new int[] MyIntArray
        {
            get
            {
                tmparray = new int[3];
                tmparray[0] = MyInt1;
                tmparray[1] = MyInt2;
                tmparray[2] = MyInt3;
                return tmparray;
            }
            set
            {
                MyInt1 = value[0];
                MyInt2 = value[1];
                MyInt3 = value[2];
            }
        }
    }

andre_swnpl wrote:

Make the variable "tmparray" private to the class like this

andre_swnpl wrote:

declare the property in the base class and then use the "new" keyword in the sub class on the same property.

Dewald wrote:

The problem comes when I'm trying to set only certain elements in the array. I would expect that, at this point, the three int member variables would hold the values 10, 40 and 30 but the set method is never called when I allocate a value to an individual element in the array as done here.

Dewald wrote:

Does anyone know how to write the get and set methods so that the array can be accessed both as an entire array or as individual elements?

Dewald wrote:

Can get and set metods be virtual (or something similar)?

Dewald wrote:

This doesn't work. It doesn't even compile

public abstract class A
{
    public abstract int Property { get; set; }
}
 
class B : A
{
    public override int Property
    {
        get
        {
            // Do Stuff
        }
        set
        {
            // Do Stuff
        }
    }
}

public class ArrayStorageClass {
   private int[] _data;
   public ArrayStorageClass() {
      _data = new int[3];
   }
   public int[] MyIntArray {
      get { return _data; }
      set {
         if (value.Length != 3) throw new ApplicationException("An array with the size of three has to be used.");
         _data = value;
      }
   }
   public int MyInt1 { get { return _data[0]; } set { _data[0] = value; } }
   public int MyInt2 { get { return _data[1]; } set { _data[1] = value; } }
   public int MyInt3 { get { return _data[2]; } set { _data[2] = value; } }
}

ArrayStorageClass storage = new ArrayStorageClass();
storage.MyIntArray[0] = 42;
storage.MyInt2 = 1;

public class ArrayEmulatorClass {
   private int _data1, _data2, _data3;
   public ArrayEmulatorClass() {}
   public int this[int index] {
      get {
         switch (index) {
            case 0: return _data1;
            case 1: return _data2;
            case 2: return _data3;
            default: throw new IndexOutOfRangeException();
         }
      }
      set {
         switch (index) {
            case 0: _data1 = value;
            case 1: _data2 = value;
            case 2: _data3 = value;
            default: throw new IndexOutOfRangeException();
         }
      }
   }
   public int MyInt1 { get { return _data1; } set { _data1 = value; } }
   public int MyInt2 { get { return _data2; } set { _data2 = value; } }
   public int MyInt3 { get { return _data3; } set { _data3 = value; } }
}

ArrayEmulatorClass emulator = new ArrayEmulatorClass();
emulator[0] = 42;
emulator.MyInt2 = 1;

public abstract class PropertyBaseClass {
   protected int _data;
   public abstract int MyProperty { get; set; }
}

public class SpecificPropertyClass : PropertyBaseClass {
   public override int MyProperty { get { return _data; } set { _data = value; } }
}