Skip to main content

Anonymous Methods in C# .NET


Anonymous Methods in C#

An anonymous method is a method which doesn’t contain any name, it is introduced in C# 2.0. It is useful when the user wants to create an inline method and also wants to pass parameter in the anonymous method like other methods. An Anonymous method is defined using the delegate keyword and the user can assign this method to a variable of the delegate type.

Syntax of Anonymous method

Anonymous methods are declared with the creation of the delegate instance, with a delegate keyword. For example
delegate(parameterList)
{
    // Code..
};

Example of Anonymous method

using System;

namespace LegalManagementSystem.Models
{
    public delegate void CsharpArticle(string article);
    public class CsharpnaijaAnonymous
    {
        public static void Main()
        {
            // An anonymous method with one parameter
            CsharpArticle p = delegate (string article)
            {
                Console.WriteLine("My favorite article in                    Csharp naija blog is: {0}",article);
            };
            p("Anonymous method in C#");
        }
    }
}

 Important Points:

·         This method is also known as inline delegate.
·         Using this method you can create a delegate object without writing separate methods.
·         This method can access variable present in the outer method. Such type of variables is known as Outer variables. As shown in the below example art is the outer variable.

You can also pass anonymous method to another method which accepts delegate as a parameter. As shown in the below example:

using System;

namespace LegalManagementSystem.Models
{
    public delegate void CsharpArticle(string article);

    public delegate void ReadArticle(string x);
    public class CsharpnaijaAnonymous
    {
        // identity method with two parameters
        public static void CsharpArticle(ReadArticle article,
                                  string articleDesc)
        {
            articleDesc = " Delegates and Events ";
            article(articleDesc);
        }
        public static void Main()
        {
            // Here anonymous method pass as 
            // a parameter in CsharpArticle method
            CsharpArticle(delegate (string articleDesc) {
                Console.WriteLine("The Anonymous method is a good concept in understanding of {0}", articleDesc);
            }, "in C#");
        }
    }
}

Notes

·         In anonymous methods, you are allowed to remove parameter-list, which means you can convert an anonymous method into a delegate.
·         The anonymous-method-block means the scope of the parameters in the anonymous method.
·         An anonymous method does not contain jump statements like ‘goto’, break, or continue.
·         An anonymous method does not access unsafe code.
·         An anonymous method does not access in, ref, and out parameter of the outer scope.
·         You cannot use an anonymous method to the left side of the ‘is’ operator.
·         You can also use an anonymous method as an event handler.

We will see how to use anonymous method as an event handler in the next article

References

1.     Geeksforgeeks
2.     TutorialPoint

Comments

Popular posts from this blog

Collections in C#

Collections in C# In our previous article , we have learned about how we can use arrays in C#. Arrays in programming are used to group a set of related objects. So one could create an array or a set of Integers, which could be accessed via one variable name. What is Collections in C#? Collections are similar to Arrays, it provides a more flexible way of working with a group of objects. In arrays, you would have noticed that you need to define the number of elements in an array beforehand. This had to be done when the array was declared. But in a collection, you don't need to define the size of the collection beforehand. You can add elements or even remove elements from the collection at any point of time. This article will focus on how we can work with the different collections available in C#. There are three distinct collection types in C#: standard generic concurrent The standard collections are found under the System.Collections. They do not store elemen...

The String.Join Method in C# Explained

The String.Join Method in C#   The string.Join concatenates the elements of a specified array or the members of a collection, using the specified separator between each element or member. Overloads of string.Join Method Description Join(Char, Object[]) Concatenates the string representations of an array of objects, using the specified separator between each member. Join(Char, String[]) Concatenates an array of strings, using the specified separator between each member. Join(String, IEnumerable<String>) Concatenates the members of a constructed IEnumerable<T> collection of type String, using the specified separator between each member. Join(String, Object[]) Concatenates the elements of an object array, using the specified separator between each element. Join(String, String[]) Concatenates all the elements of a string array, usi...

System.IO Namesapce in C#

  System.IO Namesapce in C# A  file  is a collection of data stored in a disk with a specific name and a directory path. When a file is opened for reading or writing, it becomes a  stream . The stream is basically the sequence of bytes passing through the communication path. There are two main streams: the  input stream  and the  output stream . The  input stream  is used for reading data from file (read operation) and the  output stream  is used for writing into the file (write operation). From the above definition of file, the C# provides a namespace that enable us to manipulate file in C# called System.IO.   System.IO  is a  namespace  and it contains a standard IO (input/output) types such as classes , structures , enumerations , and  delegates  to perform a read/write operations on different sources like file, memory, network, etc.   System.IO Classes The table below shows differen...