Difference between Object Vs Var Vs Dynamic Keyword

Object Vs Var Vs Dynamic Keyword

So right now in C# we have the Object class, and the var and dynamic types. At first look, they all seem to do the same job, but not really.

Then the question is, what is the difference between Object, var and dynamic? And when should we use them?

So here is the answer.

Object

The object class in C# represents the System.Object type, which is the root type in the C# class hierarchy. Generally we use this class when we cannot specify the object type at compile time, which generally happens, when we deal with interoperability.

Let's have an example. The following example explains that the variable amount, of which the type is object, but at run time we can get the actual type of that variable that is stored in the variable.




Let's perform a mathematical operation on it.



Why are we unable to perform a mathematical operation on it and instead get an error message but in the previous example we get the type of Amount as System.Int32. If the amount is a Systme.Int32 type and we can store an integer value in it then why are we unable to apply a simple mathematical operation?

Here is the reason. Actually, an object requires explicit type conversion before it can be used. We can store anything in the object type variable but for performing an operation we must type cast it. Because C# is a statically typed language so it will throw an exception when we start performing any operation on it without proper type casting.



Var

The var type was introduced in C# 3.0. It is used for implicitly typed local variables and for anonymous types. The var keyword is generally used with LINQ.

When we declare a variable as a var type, the variable's type is inferred from the initialization string at compile time.



We cannot change the type of these variables at runtime. If the compiler can't infer the type, it produces a compilation error.



Dynamic

The dynamic type was introduced in C# 4.0. The dynamic type uses System.Object indirectly but it does not require explicit type casting for any operation at runtime, because it identifies the types at runtime only.



In the code above we are assigning various types of values in the variable amount because its type is dynamic and dynamic delays determination of the type until execution. All dynamic types variables enjoy the party at runtime.

Serialization and Types of Serialization in C#.Net

Serialization:

1.Serialization is a process of converting an object into a stream of data so that it can be is easily transmittable over the network or can be continued in a persistent storage location. This storage location can be a physical file, database or ASP.NET Cache.

2.Serialization is the technology that enables an object to be converted into a linear stream of data that can be easily passed across process boundaries and machines. This stream of data needs to be in a format that can be understood by both ends of a communication channel so that the object can be serialized and reconstructed easily.

Advantage:

Using serialization is the ability to transmit data across the network in a cross-platform-compatible format, as well as saving it in a persistent or non-persistent storage medium in a non-proprietary format.

Serialization is used by Remoting, Web Services SOAP for transmitting data between a server and a client. The Remoting technology of .NET makes use of serialization to pass objects by value from one application domain to another.

De-serialization is the reverse; it is the process of reconstructing the same object later.

Types of Serialization

Serialization can be of the following types:

1.Binary Serialization
2.SOAP Serialization
3.XML Serialization

Binary Serialization:

Binary serialization is a mechanism which writes the data to the output stream such that it can be used to re-construct the object automatically. The term binary in its name implies that the necessary information that is required to create an exact binary copy of the object is saved onto the storage media.

Difference between Binary serialization and XML serialization is that Binary serialization preserves instance identity while XML serialization does not. In other words, in Binary serialization the entire object state is saved while in XML serialization only some of the object data is saved.

Binary serialization can handle graphs with multiple references to the same object; XML serialization will turn each reference into a reference to a unique object


The SOAP protocol is ideal for communicating between applications that use heterogeneous architectures. In order to use SOAP serialization in .NET we have to add a reference to System.Runtime.Serialization.Formatters.Soap in the application. The basic advantage of SOAP serialization is portability. The SoapFormatter serializes objects into SOAP messages or parses SOAP messages and extracts serialized objects from the message.

XML Serialization:

· According to MSDN, "XML serialization converts (serializes) the public fields and properties of an object or the parameters and returns values of methods, into an XML stream that conforms to a specific XML Schema definition language (XSD) document.

· XML serialization results in strongly typed classes with public properties and fields that are converted to a serial format (in this case, XML) for storage or transport. Because XML is an open standard, the XML stream can be processed by any application, as needed, regardless of platform." Implementing XML Serialization in .Net is quite simple.