Essential Books

Overloading the indexer to create a SparseArray

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By overloading the indexer you can create a class that looks and feels like an array but isn’t. It will have O(1) get and set methods, can access an element at index 100, and yet still have the size of the elements inside of it. The SparseArray class 

class SparseArray
{
    Dictionary<int, string> array = new Dictionary<int, string>();

    public string this[int i]
    {
        get
        {
            if(!array.ContainsKey(i))
            {
                return null;
            }
            return array[i];
        }
        set
        {
            if(!array.ContainsKey(i))
                array.Add(i, value);
        }
    }
}
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Indexer:
* Indexer
* A simple indexer
* Overloading the indexer to create a SparseArray
* Indexer with 2 arguments and interface
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
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20 On Algorithm for circular rotation of an array
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90 Overload Resolution
91 Preprocessor directives
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95 File and Stream IO
96 Networking
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104 Indexer
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110 Async/Await, BackgroundWorker, Task and Thread examples
111 Async Await
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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
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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