DotNetToolbox.Linq 8.1.1

DotNetToolbox.Linq

Introduction

DotNetToolbox.Linq is a powerful C# library for .NET 8, designed to enhance and extend LINQ (Language Integrated Query) capabilities. It provides a suite of utilities and extension methods to simplify complex query operations, improve performance, and add new functionalities to LINQ.

Installation

dotnet add package DotNetToolbox.Linq

Dependencies

• .NET 8

Key Features

AsyncQueryable Extensions

• Provides asynchronous versions of common LINQ operations
• Supports efficient handling of large datasets in asynchronous scenarios

Enhanced Queryable Extensions

• Extends IQueryable with additional methods for advanced querying
• Includes operations like ToIndexedList, AsIndexed, and more

Expression Manipulation

• Utilities for modifying and transforming LINQ expressions
• Includes ExpressionConversionVisitor for type-safe expression modifications

Type Mapping

• TypeMapper class for mapping between different types in LINQ expressions

Core Components

AsyncQueryable

• IAsyncQueryable<T>: Interface for asynchronous queryables
• AsyncQueryable<T>: Base implementation of IAsyncQueryable
• EmptyAsyncQueryable<T>: Represents an empty async queryable

AsyncQueryableExtensions

Provides asynchronous versions of common LINQ operations, including:

• AggregateAsync
• AllAsync
• AnyAsync
• AverageAsync
• ContainsAsync
• CountAsync
• ElementAtAsync
• FirstAsync/FirstOrDefaultAsync
• LastAsync/LastOrDefaultAsync
• MaxAsync/MinAsync
• SumAsync
• ToArrayAsync/ToListAsync/ToDictionaryAsync/ToHashSetAsync

QueryableExtensions

Extends IQueryable with additional methods:

• AsIndexed: Converts a query to an indexed sequence
• ForEach: Allows iteration over query results
• ToIndexedList: Creates a list of indexed items
• ToArray/ToList/ToHashSet with custom projections

ExpressionExtensions

• ReplaceExpressionType: Allows type-safe modification of LINQ expressions
• Apply: Applies an expression to an enumerable collection

Usage Examples

Using AsyncQueryable

IAsyncQueryable<int> asyncNumbers = AsyncQueryable.Range(1, 100);
var sum = await asyncNumbers.SumAsync();

Asynchronous LINQ Operations

var query = dbContext.Users.Where(u => u.IsActive);
var activeUserCount = await query.CountAsync();
var firstActiveUser = await query.FirstOrDefaultAsync();

Using Indexed Queries

var indexedQuery = dbContext.Products.AsIndexed();
var indexedList = await indexedQuery.ToListAsync();
foreach (var item in indexedList)
{
    Console.WriteLine($"Index: {item.Index}, Product: {item.Value.Name}");
}

Expression Type Replacement

Expression<Func<User, bool>> expr = u => u.Age > 18;
var convertedExpr = expr.ReplaceExpressionType(new TypeMapper<User, Customer>(u => new Customer { Age = u.Age }));

Contributing

Contributions to DotNetToolbox.Linq are welcome. Please ensure that your code adheres to the project's coding standards and is covered by unit tests.

License

This project is licensed under the MIT License - see the LICENSE file for details.