Essential Books

GroupBy one or multiple fields

suggest change

Lets assume we have some Film model: 

public class Film {
    public string Title { get; set; }
    public string Category { get; set; }
    public int Year { get; set; }
}

Group by Category property: 

foreach (var grp in films.GroupBy(f => f.Category)) {
    var groupCategory = grp.Key;
    var numberOfFilmsInCategory = grp.Count();
}

Group by Category and Year: 

foreach (var grp in films.GroupBy(f => new { Category = f.Category, Year = f.Year })) {
    var groupCategory = grp.Key.Category;
    var groupYear = grp.Key.Year;
    var numberOfFilmsInCategory = grp.Count();
}
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LINQ Queries:
* LINQ Queries
* Chaining methods
* First FirstOrDefault Last LastOrDefault Single and SingleOrDefault
* Except
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* JOINS
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* Zip
* 09Defining a variable inside a Linq query let keyword
* Range and Repeat
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* Basics
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* SelectMany Flattening a sequence of sequences
* Query collection by type cast elements to type
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* Enumerating the Enumerable
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* Using Range with various Linq methods
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* Any and FirstOrDefault - best practice
* GroupBy one or multiple fields
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* Joining multiple sequences
* Joining on multiple keys
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* Linq Quantifiers
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Table Of Contents
0 Getting Started With C#
1 Literals
2 Operators
3 Conditional Statements
4 Equality Operator
5 Equals and GetHashCode
6 Null-Coalescing Operator
7 Null-Conditional Operators
8 nameof Operator
9 Verbatim String
10 Common String Operations
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12 String Concatenate
13 String Manipulation
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15 String Escape Sequences
16 StringBuilder
17 Regex
18 DateTime
19 Arrays
20 On Algorithm for circular rotation of an array
21 Enum
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23 Overview of C# collections
24 GUID
25 BigInteger
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30 Value type vs Reference type
31 Built-in Types
32 Aliases of built-in types
33 Anonymous types
34 Dynamic type
35 Type Conversion
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37 Nullable types
38 Constructors and Finalizers
39 Access Modifiers
40 Interfaces
41 Static Classes
42 Singleton Implementation
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44 Partial class and methods
45 Object Initializers
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48 Named Arguments
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50 Data Annotation
51 Keywords
52 Recursion
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54 XML Documentation Comments
55 Comments and regions
56 Inheritance
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60 IDisposable interface
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63 LINQ to Objects
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69 C# 7.0 Features
70 C# 6.0 Features
71 C# 5.0 Features
72 C# 4.0 Features
73 C# 3.0 Features
74 Exception Handling
75 NullReferenceException
76 Handling FormatException
77 Read and Understand Stack trackes
78 Diagnostics
79 Overflow
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81 Using json.net
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83 Lambda expressions
84 Generic Lambda Query Builder
85 Properties
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87 INotifyPropertyChanged interface
88 Events
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91 Preprocessor directives
92 Structs
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94 Delegates
95 File and Stream IO
96 Networking
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100 Asynchronous Socket
101 Action Filters
102 Polymorphism
103 Immutability
104 Indexer
105 Checked and Unchecked
106 Stream
107 Timers
108 Stopwatches
109 Threading
110 Async/Await, BackgroundWorker, Task and Thread examples
111 Async Await
112 Synchronization Context in Async/Await
113 BackgroundWorker
114 Task Parallel Library
115 Making a variable thread safe
116 Lock Statement
117 Yield Keyword
118 Task Parallel Library TPL Dataflow Constructs
119 Functional Programming
120 Func delegates
121 Function with multiple return values
122 Binary Serialization
123 ICloneable
124 IComparable
125 Accessing Databases
126 Using SQLite
127 Caching
128 Code Contracts
129 Code Contracts and Assertions
130 Structural Design Patterns
131 Creational Design Patterns
132 Implementing Decorating Design Pattern
133 Implementing Flyweight Design Pattern
134 System.Management.Automation
135 Pointers
136 Pointers and Unsafe Code
137 Simulating C Unions with C# Structs
138 Reactive Extensions Rx
139 AsseblyInfo.cs examples
140 Creating Console Application
141 CLSCompliantAttribute
142 ObservableCollection
143 Hash Functions
144 Generating Random Numbers
145 Cryptography
146 Unsafe Code in .NET
147 C# Script
148 Runtime Compile
149 Interoperability
150 .NET Compiler Platform Roslyn
151 Creating Own MessageBox in Windows Form Application
152 Including Font Resources
153 Garbage Collector
154 Windows Communication Foundation
155 Contributors