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Update readme and bump version
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‎README.md

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@@ -15,6 +15,8 @@ The parser aims to be Database and Provider agnostic. It currently targets Netst
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* Sql Server
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* PostgreSQL
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If you intend to filter your dataset, the default configuration assumes your IQueryable uses a provider with support for .ToString() on DateTime and numeric types. Please note that EFCore will not fail but instead fall back to client evaluation if this requirement is not met. I have mixed feelings about this. I believe client evaluation should be opt-in and not opt-out.
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jQuery Datatables
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========================
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The included Dockerfile-websample builds, packages and runs the web sample project in a docker image. No tools, frameworks or runtimes are required on the host machine. The image has been published to docker for your convenience.
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docker run -p 80:80 garvincasimir/datatables-aspnet-core-sample:0.0.2
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docker run -p 80:80 garvincasimir/datatables-aspnet-core-sample:0.0.2
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Custom Filter Expressions
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========================
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The parser builds a set of expressions based on the settings and filter text sent from Datatables. The end result is a *WHERE* clause which looks something like this:
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```
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FROM [People] AS [val]
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WHERE ((((CASE
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WHEN CHARINDEX(N'cromie', LOWER([val].[FirstName])) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END | CASE
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WHEN CHARINDEX(N'cromie', LOWER([val].[LastName])) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'cromie', LOWER(CONVERT(VARCHAR(100), [val].[BirthDate]))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'cromie', LOWER(CONVERT(VARCHAR(100), [val].[Weight]))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'cromie', LOWER(CONVERT(VARCHAR(11), [val].[Children]))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) = 1
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```
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In the above example, each of the case statements will attempt to find the filter text 'cromie' within a string representation of the properties from *T*. The exact mechanics and syntax will vary by provider and db engine but this is an example of the actual query sent to your backend database.
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The expression generated by the parser looks like this:
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```
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where val.FirstName.ToLower().Contains("cromie") || val.LastName.ToLower().Contains("cromie") || val.BirthDate.ToString().ToLower().Contains("cromie") || val.Weight.ToString().ToLower().Contains("cromie") || val.Children.ToString().ToLower().Contains("cromie")
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```
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What is missing in the above expression is the ability to format dates to match the client side. So it may seem strange to a user if they enter a date in the filter text box and no results are returned. It would be nice if providers just supported *DateTime.ToString(string format)* right? Even if they did, the format strings expected by db engines are not consistent at all. As a result, I decided to expose some of the internals of the parser and allow library users to substitute .ToString() with a custom expression.
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For example, if your provider does support *DateTime.ToString(string format)*, you can substitute .ToString() with that expression after initializing the parser. This must be explicitly called for each applicable property.
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```
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var parser = new Parser<Person>(p, context.People)
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.SetConverter(x => x.BirthDate, x => x.BirthDate.ToString("M/dd/yyyy"))
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.SetConverter(x => x.LastUpdated, x => x.LastUpdated.ToString("M/dd/yyyy"));
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```
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**EF Core 2**
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In EF Core 2 you can map user defined and system scalar valued functions and use them for formatting. The following is an example for SQL Server >= 2012.
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PersonContext.cs
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```
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using Microsoft.EntityFrameworkCore;
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using System;
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namespace DataTablesParser.Tests
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{
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public class PersonContext : DbContext
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{
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public PersonContext(){ }
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public PersonContext(DbContextOptions<PersonContext> options)
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: base(options){ }
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//Sql Server >= 2012
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//https://docs.microsoft.com/en-us/sql/t-sql/functions/format-transact-sql
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[DbFunction]
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public static string Format(DateTime data,string format)
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{
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throw new Exception();
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}
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public DbSet<Person> People { get; set; }
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}
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}
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```
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Parser initialization
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```
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var parser = new Parser<Person>(p, context.People)
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.SetConverter(x => x.BirthDate, x => PersonContext.Format(x.BirthDate,"M/dd/yyyy"));
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```
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The *WHERE* clause now looks like this:
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```
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WHERE ((((CASE
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WHEN CHARINDEX(N'9/03/1953', LOWER([val].[FirstName])) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END | CASE
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WHEN CHARINDEX(N'9/03/1953', LOWER([val].[LastName])) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'9/03/1953', LOWER(Format([val].[BirthDate], N'M/dd/yyyy'))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'9/03/1953', LOWER(CONVERT(VARCHAR(100), [val].[Weight]))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) | CASE
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WHEN CHARINDEX(N'9/03/1953', LOWER(CONVERT(VARCHAR(11), [val].[Children]))) > 0
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THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT)
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END) = 1
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```
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For examples using MySQL and PostgreSQL please see the test project
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Installation
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========================
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* The diff for your pull request should only show changes related to your fix/addition (Some editors create unnecessary changes).
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* When possible include tests that cover the features/changes in your pull request
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* Before you submit make sure the existing tests pass with your changes
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* Also, issues that are accompanied by failing tests will probably get handleded quicker
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* Also, issues that are accompanied by failing tests will probably get handled quicker
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Contact
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========================

‎src/DatatablesParser/DatatablesParser.csproj

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<TargetFramework>netstandard1.3</TargetFramework>
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<AssemblyName>DatatablesParser</AssemblyName>
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<PackageId>DatatablesParser-core</PackageId>
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<PackageVersion>1.0.0</PackageVersion>
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<PackageVersion>1.1.0</PackageVersion>
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<PackageRequireLicenseAcceptance>false</PackageRequireLicenseAcceptance>
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<PackageTags>C# Datatables Datatables.net javascript parser json Linq entity framework asp.net mvc grid table database query builder core</PackageTags>
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<PackageProjectUrl>https://github.com/garvincasimir/csharp-datatables-parser</PackageProjectUrl>

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