Memoizer

This is a quick and easy way of adding Memoization/Caching to your C# project.

// Result will be cached for the lifetime of this application
[Cache]
public string HelloWorld() => "Hello World!";

// Result will be cached for 500 Milliseconds
[Cache(500)]
public string HelloWorld() => "500 Millisecond Cache";

// Result will be cached for 5 seconds
[Cache(5, Time.Second)]
public string HelloWorld() => "5 Second Cache";

Calls to cached method with matching arguments will be cached meaning only the first call with a unique set or args will execute the internal code.

Installation

Add the NuGet package to your project.

Install-Package Memoizer.NETStandard

Why

Memoization is an optimization technique used primarily to speed up computer programs by storing the results of expensive function calls and returning the cached result when the same inputs occur again.

Usage Example

There are many use cases where it is appropriate to cache the result of a method call. A popular use case is a method that returns the Nth Fibonacci number. The time taken increases exponentially as you increase N.

With Caching

[Cache]
public BigInteger Fib(int n)
{
    if (n < 2) return n;
    return Fib(n - 1) + Fib(n - 2);
}
Fib(5); // 0.003s
Fib(50); // 0.003s
Fib(300); // 0.010s
Fib(1000); // 0.013s

Without Caching

// Brute Force method that does not Use Memoization
public BigInteger Fib(int n)
{
    if (n < 2) return n;
    return Fib(n - 1) + Fib(n - 2);
}

Fib(5); // 0.003s
Fib(50); // 977s (16 Minutes)
Fib(300); // Come back tomorrow
Fib(1000); // Years!!

As you can see the use of Caching in this example allows us to actually work out the Fib of 1000 in neglegeable time.