Book Image

Beginning C# 7 Hands-On ??? Advanced Language Features

By : Tom Owsiak
Book Image

Beginning C# 7 Hands-On ??? Advanced Language Features

By: Tom Owsiak

Overview of this book

Beginning C# 7 Hands-On – Advanced Language Features assumes that you’ve mastered the basic elements of the C# language and that you're now ready to learn the more advanced C# language and syntax, line by line, in a working Visual Studio environment. You'll learn how to code advanced C# language topics including generics, lambda expressions, and anonymous methods. You'll learn to use query syntax to construct queries and deploy queries that perform aggregation functions. Work with C# and SQL Server 2017 to perform complex joins and stored procedures. Explore advanced file access methods, and see how to serialize and deserialize objects – all by writing working lines of code that you can run within Visual Studio. This book is designed for beginner C# developers who have mastered the basics now, and anyone who needs a fast reference to using advanced C# language features in practical coding examples. You'll also take a look at C# through web programming with web forms. By the time you’ve finished this book, you’ll know all the critical advanced elements of the C# language and how to program everything from C# generics to XML, LINQ, and your first full MVC web applications. These are the advanced building blocks that you can then combine to exploit the full power of the C# programming language, line by line.
Table of Contents (35 chapters)
Title Page
Credits
About the Author
www.PacktPub.com
Customer Feedback
Preface

Creating an array


There is a lot of code to enter in this chapter, but it's mechanical. First, we will create an array, so enter the following between the curly braces under the line beginning with protected void Button1_Click...:

IEnumerable<int> scores = new int[] { 45, 98, 99, 78, 89, 87, 77, 67, 71, 81 };

Here, IEnumerable is the data type and scores is the name of the array. It doesn't matter what values you put into the array.

Averaging the values in a list

Now, first we will find an average of this list. So, enter the following next:

var goodStudentAverage = (from score in scores where score >= 90 select score).Average();

We will select students who score 90 or above. Imagine, those are the semester grades for several students. So, in the preceding line, we're saying where the score is >=90, select that score. This is a query that you can write in a single line. In this context, score is the range variable, scores is the array, and the condition that selects is where score=...