New Features of C# 6.0

New Features of C# 6.0

• Initialization of Dictionary – Dictionary initializer in C# 6.0
• Null – Conditional Operators in C# 6.0
• Using nameof Operator in C# 6.0
• Conditional Exception Handling – Exception Filters in C# 6.0
• Using await in a catch or finally block – in C# 6.0
• Expression – Bodied Methods in C# 6.0
• Simplify Static Member Access – Using Statement With Static Classes in C# 6.0
• Easily format strings – String interpolation in C# 6.0
• Initialize Auto-Property in C# 6.0
• Getter Only Auto-Property in C# 6.0

Tips to improve performance of C# code

Tips to improve performance of C# code

• Choose your data type before using it
• Use For loop instead of foreach
• Choose when to use a class and when to use a structure
• Always use Stringbuilder for String concatenation operations
• Choose best way to assign class data member
• Boxing and UnBoxing
• ‘as’ versus type casting
• Control overflow checking
•  Using readonly versus const
• Avoid producing a lot of garbage
• Avoid using finalizers when possible
• Recycle and/ or cache objects
• Reduce class hierarchy
• Avoid explicitly calling the Garbage Collector
• Avoid synchronization
• Use Lazy Evaluation
•  Optimized classes
•  Explicitly close resources
• Limit number of threads
• Ternary Operator (?:)
•  Null-Coalesce Operator (??)
• Namespace Alias Qualifier
• Object Initializers
• Nullable Types
• Type Inference
• Lambda Expressions

Volatile -- C# Keyword

volatile -- C# Keyword

• The volatile modifier is usually used for a field that is accessed by multiple threads without using the lock statement to serialize access.
• The volatile keyword can be applied to fields of these types:
• Reference types.
• Pointer types (in an unsafe context). Note that although the pointer itself can be volatile, the object that it points to cannot. In other words, you cannot declare a "pointer to volatile."
• Types such as sbyte, byte, short, ushort, int, uint, char, float, and bool.
• An enum type with one of the following base types: byte, sbyte, short, ushort, int, or uint.
• Generic type parameters known to be reference types.
• IntPtr and UIntPtr.

public volatile <data type> <Var Name>;

virtual -- C# Keyword

virtual -- C# Keyword
         The virtual keyword is used to modify a method, property, indexer, or event declaration and allow for it to be overridden in a derived class.

 public virtual <Data Type> <Method Name>()
{
///Code
  return <Value>
}

unsafe -- C# Keyword

unsafe -- C# Keyword
           The unsafe keyword denotes an unsafe context, which is required for any operation involving pointers.

Without  Parameter

unsafe
{
    // Unsafe context: can use pointers here.
}

With Parameter(s)

unsafe static void <Method Name>(<data Type> <var name>)
{
    // Unsafe context: can use pointers here.
}

static -- C# Keyword

static  -- C# Keyword

• Use the static modifier to declare a static member, which belongs to the type itself rather than to a specific object.
•  The static modifier can be used with classes, fields, methods, properties, operators, events, and constructors, but it cannot be used with indexers, destructors, or types other than classes.

static class <Class Name>
    {
        public static void <Method Name>() { /*...*/ }
        public static void <Method Name>() { /*...*/  }
    }

sealed -- C# Keyword

sealed  -- C# Keyword

•  When applied to a class, the sealed modifier prevents other classes from inheriting from it.
•   In the following example, class B inherits from class A, but no class can inherit from class B.

class A {}  
sealed class B : A {}

readonly -- C# Keyword

readonly -- C# Keyword

•  The readonly keyword is a modifier that you can use on fields.
•   When a field declaration includes a readonly modifier, assignments to the fields introduced by the declaration can only occur as part of the declaration or in a constructor in the same class.

readonly <data Type> <var Name>;

override -- C# Keyword

override -- C# Keyword

•  The override modifier is required to extend or modify the abstract or virtual implementation of an inherited method, property, indexer, or event.
• An override declaration cannot change the accessibility of the virtual method.
• Both the override method and the virtual method must have the same access level modifier.
• You cannot use the new, static, or virtual modifiers to modify an override method.

out -- C# Keyword

out -- C# Keyword

• This keyword implemented from VS 2010
•  The out keyword specifies that the type parameter is covariant.
• You can use the out keyword in generic interfaces and delegates.

interface <interface Name><out R> { }