# DynamicLinq
Adds extensions to Linq to offer dynamic queryables.
## Roadmap
Check "Projects" section of github to see whats going on.
https://github.com/PoweredSoft/DynamicLinq/projects/1
## Download
Full Version | NuGet | NuGet Install
------------ | :-------------: | :-------------:
PoweredSoft.DynamicLinq | [](https://www.nuget.org/packages/PoweredSoft.DynamicLinq/) | ```PM> Install-Package PoweredSoft.DynamicLinq```
PoweredSoft.DynamicLinq.EntityFramework | [](https://www.nuget.org/packages/PoweredSoft.DynamicLinq.EntityFramework/) | ```PM> Install-Package PoweredSoft.DynamicLinq.EntityFramework```
## Samples
Complex Query
```csharp
query = query.Query(q =>
{
q.Compare("AuthorId", ConditionOperators.Equal, 1);
q.And(sq =>
{
sq.Compare("Content", ConditionOperators.Equal, "World");
sq.Or("Title", ConditionOperators.Contains, 3);
});
});
```
### Shortcuts
Shortcuts allow to avoid specifying the condition operator by having it handy in the method name
```csharp
queryable.Query(t => t.Contains("FirstName", "Dav").OrContains("FirstName", "Jo"));
```
> You may visit this test for more examples: https://github.com/PoweredSoft/DynamicLinq/blob/master/PoweredSoft.DynamicLinq.Test/ShortcutTests.cs
### Simple Query
```csharp
query.Where("FirstName", ConditionOperators.Equal, "David");
```
### Grouping Support
```csharp
TestData.Sales
.AsQueryable()
.GroupBy(t => t.Path("ClientId"))
.Select(t =>
{
t.Key("TheClientId", "ClientId");
t.Count("Count");
t.LongCount("LongCount");
t.Sum("NetSales");
t.Average("Tax", "TaxAverage");
t.Aggregate("Tax", SelectTypes.Average, "TaxAverage2"); // Starting 1.0.5
t.ToList("Sales");
});
```
> Is equivalent to
```csharp
TestSales
.GroupBy(t => new { t.ClientId })
.Select(t => new {
TheClientId = t.Key.ClientId,
Count = t.Count(),
LongCount = t.LongCount(),
NetSales = t.Sum(t2 => t2.NetSales),
TaxAverage = t.Average(t2 => t2.Tax),
TaxAverage2 = t.Average(t2 => t2.Tax),
Sales = t.ToList()
});
```
### Empty Group By
This is common to create aggregate totals.
```csharp
someQueryable.EmptyGroupBy(typeof(SomeClass));
```
> Is equivalent to
```csharp
someQueryableOfT.GroupBy(t => true);
```
### Count shortcut
```csharp
IQueryable someQueryable = ;
someQueryable.Count();
```
> Is equivalent to
```csharp
IQueryable someQueryableOfT = ;
someQsomeQueryableOfTueryable.Count();
```
### Select
> Note **PathToList** has been renamed to just **ToList** it seemed redudant, sorry for breaking change.
```csharp
var querySelect = query.Select(t =>
{
t.NullChecking(true); // not obligated but usefull for in memory queries.
t.ToList("Posts.Comments.CommentLikes", selectCollectionHandling: SelectCollectionHandling.Flatten);
t.Path("FirstName");
t.Path("LastName", "ChangePropertyNameOfLastName");
});
```
### In Support
You can filter with a list, this will generate a contains with your list.
```csharp
var ageGroup = new List() { 28, 27, 50 };
Persons.AsQueryable().Query(t => t.In("Age", ageGroup));
```
### String Comparision Support
```csharp
Persons.AsQueryable().Query(t => t.Equal("FirstName", "DAVID", stringComparision: StringComparison.OrdinalIgnoreCase));
```
You may visit this test for more examples:
https://github.com/PoweredSoft/DynamicLinq/blob/master/PoweredSoft.DynamicLinq.Test/StringComparision.cs
### Simple Sorting
```csharp
query = query.OrderByDescending("AuthorId");
query = query.ThenBy("Id");
```
### Collection Filtering
You don't have to Worry about it.
The library will do it for you.
```csharp
var query = authors.AsQueryable();
query = query.Query(qb =>
{
qb.NullChecking();
// you can specify here which collection handling you wish to use Any and All is supported for now.
qb.And("Posts.Comments.Email", ConditionOperators.Equal, "john.doe@me.com", collectionHandling: QueryCollectionHandling.Any);
});
```
### Null Checking is automatic (practical for in memory dynamic queries)
```csharp
var query = authors.AsQueryable();
query = query.Query(qb =>
{
qb.NullChecking();
qb.And("Posts.Comments.Email", ConditionOperators.Equal, "john.doe@me.com", collectionHandling: QueryCollectionHandling.Any);
});
```
### Using Query Builder
```csharp
// subject.
var posts = new List()
{
new Post { Id = 1, AuthorId = 1, Title = "Hello 1", Content = "World" },
new Post { Id = 2, AuthorId = 1, Title = "Hello 2", Content = "World" },
new Post { Id = 3, AuthorId = 2, Title = "Hello 3", Content = "World" },
};
// the query.
var query = posts.AsQueryable();
var queryBuilder = new QueryBuilder(query);
queryBuilder.Compare("AuthorId", ConditionOperators.Equal, 1);
queryBuilder.And(subQuery =>
{
subQuery.Compare("Content", ConditionOperators.Equal, "World");
subQuery.Or("Title", ConditionOperators.Contains, 3);
});
query = queryBuilder.Build();
```
### Entity Framework
Using PoweredSoft.DynamicLinq.EntityFramework it adds an helper that allows you to do the following.
```csharp
var context = new ();
var queryable = context.Query(typeof(Author), q => q.Compare("FirstName", ConditionOperators.Equal, "David"));
var result = queryable.ToListAsync().Result;
var first = result.FirstOrDefault() as Author;
Assert.AreEqual(first?.FirstName, "David");
```
### How it can be used in a web api
```csharp
[HttpGet][Route("FindClients")]
public IHttpActionResult FindClients(string filterField = null, string filterValue = null,
string sortProperty = "Id", int? page = null, int pageSize = 50)
{
var ctx = new MyDbContext();
var query = ctx.Clients.AsQueryable();
if (!string.IsNullOrEmpty(filterField) && !string.IsNullOrEmpty(filterValue))
query = query.Query(t => t.Contains(filterField, filterValue)).OrderBy(sortProperty);
// count.
var clientCount = query.Count();
int? pages = null;
if (page.HasValue && pageSize > 0)
{
if (clientCount == 0)
pages = 0;
else
pages = clientCount / pageSize + (clientCount % pageSize != 0 ? 1 : 0);
}
if (page.HasValue)
query = query.Skip((page.Value-1) * pageSize).Take(pageSize);
var clients = query.ToList();
return Ok(new
{
total = clientCount,
pages = pages,
data = clients
});
}
```