Philiprehberger.Specification 0.1.7

dotnet add package Philiprehberger.Specification --version 0.1.7
                    
NuGet\Install-Package Philiprehberger.Specification -Version 0.1.7
                    
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="Philiprehberger.Specification" Version="0.1.7" />
                    
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageVersion Include="Philiprehberger.Specification" Version="0.1.7" />
                    
Directory.Packages.props
<PackageReference Include="Philiprehberger.Specification" />
                    
Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.
paket add Philiprehberger.Specification --version 0.1.7
                    
#r "nuget: Philiprehberger.Specification, 0.1.7"
                    
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
#:package Philiprehberger.Specification@0.1.7
                    
#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package.
#addin nuget:?package=Philiprehberger.Specification&version=0.1.7
                    
Install as a Cake Addin
#tool nuget:?package=Philiprehberger.Specification&version=0.1.7
                    
Install as a Cake Tool

Philiprehberger.Specification

CI NuGet Last updated

Specification pattern implementation for composable, reusable query filters.

Installation

dotnet add package Philiprehberger.Specification

Usage

Define Specifications

using Philiprehberger.Specification;
using System.Linq.Expressions;

public class IsActive : Specification<User>
{
    public override Expression<Func<User, bool>> ToExpression()
        => user => user.IsActive;
}

public class HasMinimumAge : Specification<User>
{
    private readonly int _minimumAge;

    public HasMinimumAge(int minimumAge) => _minimumAge = minimumAge;

    public override Expression<Func<User, bool>> ToExpression()
        => user => user.Age >= _minimumAge;
}

Compose Specifications

var isActive = new IsActive();
var isAdult = new HasMinimumAge(18);

// Combine with And, Or, Not
var activeAdult = isActive.And(isAdult);
var inactiveOrMinor = isActive.Not().Or(isAdult.Not());

Check Entities

var spec = new IsActive().And(new HasMinimumAge(18));

bool satisfies = spec.IsSatisfiedBy(user);

Filter Queryables

var spec = new IsActive().And(new HasMinimumAge(18));

// Extension method
IQueryable<User> results = dbContext.Users.Where(spec);

// Or via evaluator
IQueryable<User> results = SpecificationEvaluator.Evaluate(dbContext.Users, spec);

Implicit Conversion

Expression<Func<User, bool>> expr = new IsActive();
var results = dbContext.Users.Where(expr);

API

Specification<T>

Member Description
ToExpression() Convert to a LINQ expression tree
IsSatisfiedBy(T entity) Check if an entity satisfies the specification
implicit operator Expression<Func<T, bool>> Implicit conversion to expression

SpecificationExtensions

Method Description
And<T>(Specification<T>, Specification<T>) Combine with logical AND
Or<T>(Specification<T>, Specification<T>) Combine with logical OR
Not<T>(Specification<T>) Negate with logical NOT

QueryableExtensions

Method Description
Where<T>(IQueryable<T>, Specification<T>) Filter a queryable using a specification

SpecificationEvaluator

Method Description
Evaluate<T>(IQueryable<T>, Specification<T>) Apply a specification to a queryable source

Development

dotnet build src/Philiprehberger.Specification.csproj --configuration Release

Support

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License

MIT

Product Compatible and additional computed target framework versions.
.NET net8.0 is compatible.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed.  net9.0 was computed.  net9.0-android was computed.  net9.0-browser was computed.  net9.0-ios was computed.  net9.0-maccatalyst was computed.  net9.0-macos was computed.  net9.0-tvos was computed.  net9.0-windows was computed.  net10.0 was computed.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-windows was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.
  • net8.0

    • No dependencies.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last Updated
0.1.7 124 4/1/2026
0.1.6 109 3/25/2026
0.1.5 106 3/25/2026
0.1.4 109 3/23/2026
0.1.3 110 3/17/2026
0.1.2 126 3/16/2026
0.1.1 114 3/16/2026
0.1.0 119 3/16/2026