C#2005 DataType

This is the content of my today's study..........

C# Datatype:-

We can say three types of Datatype in C#: Value type,Reference type,pointer type
1.Value type uses stack,and have discrete values stores in it; It does not implement data hiding features;
2.Reference type:stored in heap , .Net framework support two reference types which are Object and String;Object is the base type for Value type and reference type;
They implement data hiding concept, and their data can be manipulated by using methods;
3.Pointer type: they are not type safe, they are not controlled by G.C. while reference type are in control of GC;
Arithematic operation can be performed on Pointer type while it is not possible on reference type;
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All variables (Value type and reference type) are the class variable first.
so they can be used as an object anywhere in the system;
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Nullable Types
C# supports nullable types. nullable is a struct which has two public members.
One is Hasvalue() which return true or false.and other one is value which returns the value only if HasValue() is true , else while accessing the value property it throw an exception;
They can be used as follows:-
System.Nullable< a > = 10;
or
int? a=10; or int? a=null;
while We can not write int a=null;, this will give an error that a is not nullable type.

--> They can be used with Value type only not with reference type;
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SOme Note POints:-

structure elements are protected by default while class members are private by default in C#;
Structure can contain constructor,destructor,methods,properties .
structure element can not be initialized by any given value in structure.while class variable initialized by default values.
C# Class always created in heap while structure can be created in Heap or stack.
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Datatype.MaxValue amd Datatype.MinValue can be used to determine the range of the datatype. while these thing can not be implemented in some Datatype like bool;
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Boxing:-
It is a concept of converting a value type into Reference type.
It is a expensive process, it uses some process cycle to do so
and data reside at two place and may have contradictory state at the same time.
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C# Supports Jagged arrays(Different rows can have different number of column )
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This is what i studied today.........
Feedback and comments are required to improve....................



Thanks & Regards
Bheeshma P. Nayak