通过fsharp探索Enterprise Library 6 DataBase 1.3 Sqlite

使用Enterprise Library就是为了尽可能少的开发常用组件。数据库在选择的过程中常会面临部署，版权，个人喜好等诸多考量。最佳的处理方法就是添加一层数据抽象层，再切换Enterprise的过程中进行无缝衔接。由于我的笔记本跑的越来越慢，又想尝试一下使用Sqlite所以，就用Sqlite做例子。

我用的是Enterprise Library 6.0原本以为只需要简单的配置就可以进行实验，没想到GitHub上Sqlite提供的Sqlite兼容组件到Enterprise Library 4.1后就不提供了。我用网上的配置文件进行实验，果然有不支持的类提示。原来总以为是没有提供正确的Database TypeProvider，试了很多次都没有结果。总是出错时最好的解决办法就是休息，然后到处看看。果然已经有高人在codeproject上试出来了。自己扩展了
类，以后再研究。先回到正题。

我在配置文件中用了Sqlite自带的测试数据库。通过发送sql语句查询数据库的代码几乎没有改动就成功的获取了希望的结果。

配置文件

<?xml version="1.0"?>
<configuration>
  <configSections>
    <section name="dataConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data, Version=6.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
    <section name="connectionStrings" type="System.Configuration.ConnectionStringsSection, System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" requirePermission="true" />
  </configSections>
  <dataConfiguration defaultDatabase="sss" >
	<providerMappings>
		<add databaseType="EntLibContrib.Data.SQLite.SQLiteDatabase, EntLibContrib.Data.SQLite, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" name="System.Data.SQLite" />
	</providerMappings>
  </dataConfiguration>
  <system.data>
  </system.data>
  <connectionStrings>
    <add name="ExampleDatabase" connectionString="Data Source=(localdb)\v11.0;AttachDbFilename=E:\WorkHell\fsharp-practise\EnterpriseLibraryPractise\DataAccessExamples.mdf;Integrated Security=True"
      providerName="System.Data.SqlClient" />
    <add name="AsyncExampleDatabase" connectionString="Data Source=(localdb)\v11.0;Asynchronous Processing=true;AttachDbFilename=|DataDirectory|\DataAccessExamples.mdf;Integrated Security=True"
      providerName="System.Data.SqlClient" />
    <add name="DataAccessExample.Properties.Settings.DataAccessExamplesConnectionString"
      connectionString="Data Source=(localdb)\v11.0;AttachDbFilename=|DataDirectory|\DataAccessExamples.mdf;Integrated Security=True"
      providerName="System.Data.SqlClient" />
    <add name="sss"
      connectionString="Data Source=E:\WorkHell\fsharp-practise\EnterpriseLibraryPractise\dbdemos.db3;Version=3;"
      providerName="System.Data.SQLite" />
  </connectionStrings>
</configuration>

代码

#if INTERACTIVE
#I @"E:\WorkHell\fsharp-practise\packages"
#r @"EnterpriseLibrary.Data.6.0.1304.0\lib\NET45\Microsoft.Practices.EnterpriseLibrary.Data.dll"
#r @"EnterpriseLibrary.Common.6.0.1304.0\lib\NET45\Microsoft.Practices.EnterpriseLibrary.Common.dll"
#r @"System.Data.SQLite.Core.1.0.94.0\lib\net45\System.Data.SQLite.dll"
#r @"EntLibContrib.Data.SQLite.dll"
#r "System"
#r "System.Data"
#r "System.Configuration"
#endif

open System
open System.Data
open System.Data.Common
open System.Data.SqlClient
open Microsoft.Practices.EnterpriseLibrary.Data
open Microsoft.Practices.EnterpriseLibrary.Common.Configuration
open Microsoft.Practices.EnterpriseLibrary.Data.Sql
open Microsoft.Practices.EnterpriseLibrary.Data.Configuration
open System.Threading
open System.Threading.Tasks
open System.Configuration
open System.Data.SQLite
open EntLibContrib.Data.SQLite

let DisplayRowValue (reader:IDataReader) =
    while reader.Read() do
        for i = 0 to reader.FieldCount-1 do
            Console.WriteLine("{0}={1}", reader.GetName(i), reader.[i].ToString())
    Console.WriteLine()

let path = __SOURCE_DIRECTORY__ + "\FsiApp.config"
let fileMap = ConfigurationFileMap(path)
let config = ConfigurationManager.OpenMappedMachineConfiguration(fileMap)
let factory = new DatabaseProviderFactory(fun s -> config.GetSection(s))

let defaultDB = factory.Create("sss")
let reader = defaultDB.ExecuteReader(CommandType.Text, "select * from orders")
DisplayRowValue reader

以上