default value for different data type in C#

In C# there are different data type and they use some default value when we declare a variable. When we define a variable of type int or Int32 say int score; so what is the value of score, will it be null or zero, in the same way if we create a variable of type string/String what value it holds by default. I was working on a project and used following code

int score;
If (somecondition == true)
   score = somevalue;

And I was expecting if condition is true then score will be assigned otherwise it would be null but I was wrong because default value for an int variable is zero (0). Finally I changed my code, and forcibly make my score variable to nullable.

Int? score;
If (somecondition == true)
   score = somevalue;

On the other hand String is by default null and not an empty string also string not a value type in C# but its a reference type.

Here is the some mostly used data type and their default values

 DATE TYPE  |  DEFAULT VALIE
------------------------------------
 String     |  null
 bool       |  false
 char       |  '\0'
 decimal    |  0.0M
 double     |  0.0D
 enum       | The value produced by the expression (E)0,
                      where E is the enum identifier.
 float      |  0.0F
 int        |  0
 long       |  0L
 sbyte      |  0
 short      |  0
 struct     |  The value produced by setting all value-type fields to their 
                   default values and all reference-type fields to null.
 uint       |  0
 ulong      |  0
 ushort     |  0
Ali Adravi Having 13+ years of experience in Microsoft Technologies (C#, ASP.Net, MVC and SQL Server). Worked with Metaoption LLC, for more than 9 years and still with the same company. Always ready to learn new technologies and tricks.
  • c#
By Ali Adravi On 27 Mar, 13  Viewed: 2,599

Other blogs you may like

Polymorphism in C# with example

Polymorphism is derived from two Latin words, 1. Poly means many 2. Marphose means forms. By using inheritance, a class can be used as many types, say we have a Person which may be a Professor, may be a Student, may be Clerk. So in this article we will see some example of Polymorphism. When we... By Hamden   On 01 Jun 2013  Viewed: 4,548

How to create windows service in C# visual studio 2010

Creating windows service in C# is really easy but when we need to create first time we face many problems so in this post we will try to learn everything about window service. In this article we will create a windows service which will run after a particular interval, and time should be... By Ali Adravi   On 30 Apr 2013  Viewed: 8,610

Covariance and Contravariance in C# 4.0 with example

C# the language, right from the very beginning is always supported covariance and contravariance but in most simple scenario, now in C# 4.0 we have full support of covariance and contravariance in all circumstances, generic interface and generic delegates, other C# types already support from first... By Ali Adravi   On 29 Mar 2013  Viewed: 4,977

enum in C# and conversion

An enumeration type (also known an enumeration or an enum) provides an efficient way to define a set of named integral constants that may be assigned to a variable to make programming clear, understandable and manageable. There are ways of using, like how to use enum in switch and case statement,... By Hamden   On 27 Mar 2013  Viewed: 4,525

Dynamic vs var in C# with example

When we have var which dynamically holds any type or value so why we need dynamic type, what are the differences and situations where we can use dynamic rather than var, there were some question in my mind so I explored more which I want to share here. There are two things, static type and... By Nathan Armour   On 26 Mar 2013  Viewed: 3,204