Anonymous Types
Anonymous types provide a convenient way to encapsulate a set of read-only properties into a single object without having to first explicitly define a type. The type name is generated by the compiler and is not available at the source code level. The type of the properties is inferred by the compiler. The following example shows an anonymous type being initialized with two properties called Amount and Message.
var v = new { Amount = 108, Message = "Hello" };
Anonymous types are class types that consist of one or more public read-only properties. No other kinds of class members such as methods or events are allowed. An anonymous type cannot be cast to any interface or type except for object.
Anonymous types are reference types that derive directly from object. The compiler gives them a name although your application cannot access it. From the perspective of the common language runtime, an anonymous type is no different from any other reference type, except that it cannot be cast to any type except for object.
The most common scenario is to initialize an anonymous type with some properties from another type. In the following example, assume a class that is named Product that includes Color and Price properties together with several other properties that you are not interested in. Products is a collection of Product objects. The anonymous type declaration starts with the new keyword. It initializes a new type that uses only two properties from Product. This causes a smaller amount of data to be returned in the query.
If you do not specify member names in the anonymous type, the compiler gives the anonymous type members the same name as the property being used to initialize them. You must provide a name to a property that is being initialized with an expression.
var productQuery =
from prod in products
select new { prod.Color, prod.Price };
foreach (var v in productQuery)
{
Console.WriteLine("Color={0}, Price={1}", v.Color, v.Price);
}
Anonymous Method
Creating anonymous methods is essentially a way to pass a code block as a delegate parameter.
By using anonymous methods, you reduce the coding overhead in instantiating delegates by eliminating the need to create a separate method.
The scope of the parameters of an anonymous method is the anonymous-method-block.
Unlike local variables, the lifetime of the outer variable extends until the delegates that reference the anonymous methods are eligible for garbage collection.
A reference to n is captured at the time the delegate is created.
An anonymous method cannot access the ref or out parameters of an outer scope.
No unsafe code can be accessed within the anonymous-method-block.
It is an error to have a jump statement, such as goto, break, or continue, inside the anonymous method block whose target is outside the block. It is also an error to have a jump statement, such as goto, break, or continue, outside the anonymous method block whose target is inside the block.
The local variables and parameters whose scope contain an anonymous method declaration are called outer or captured variables of the anonymous method.
Anonymous types provide a convenient way to encapsulate a set of read-only properties into a single object without having to first explicitly define a type. The type name is generated by the compiler and is not available at the source code level. The type of the properties is inferred by the compiler. The following example shows an anonymous type being initialized with two properties called Amount and Message.
var v = new { Amount = 108, Message = "Hello" };
Anonymous types are class types that consist of one or more public read-only properties. No other kinds of class members such as methods or events are allowed. An anonymous type cannot be cast to any interface or type except for object.
Anonymous types are reference types that derive directly from object. The compiler gives them a name although your application cannot access it. From the perspective of the common language runtime, an anonymous type is no different from any other reference type, except that it cannot be cast to any type except for object.
The most common scenario is to initialize an anonymous type with some properties from another type. In the following example, assume a class that is named Product that includes Color and Price properties together with several other properties that you are not interested in. Products is a collection of Product objects. The anonymous type declaration starts with the new keyword. It initializes a new type that uses only two properties from Product. This causes a smaller amount of data to be returned in the query.
If you do not specify member names in the anonymous type, the compiler gives the anonymous type members the same name as the property being used to initialize them. You must provide a name to a property that is being initialized with an expression.
var productQuery =
from prod in products
select new { prod.Color, prod.Price };
foreach (var v in productQuery)
{
Console.WriteLine("Color={0}, Price={1}", v.Color, v.Price);
}
Anonymous Method
Creating anonymous methods is essentially a way to pass a code block as a delegate parameter.
By using anonymous methods, you reduce the coding overhead in instantiating delegates by eliminating the need to create a separate method.
The scope of the parameters of an anonymous method is the anonymous-method-block.
Unlike local variables, the lifetime of the outer variable extends until the delegates that reference the anonymous methods are eligible for garbage collection.
A reference to n is captured at the time the delegate is created.
An anonymous method cannot access the ref or out parameters of an outer scope.
No unsafe code can be accessed within the anonymous-method-block.
It is an error to have a jump statement, such as goto, break, or continue, inside the anonymous method block whose target is outside the block. It is also an error to have a jump statement, such as goto, break, or continue, outside the anonymous method block whose target is inside the block.
The local variables and parameters whose scope contain an anonymous method declaration are called outer or captured variables of the anonymous method.
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