这是我最终发现的。这是一个非常具体的问题,涉及使用更多属性扩展元素以及在实现时如何处理它们提供者框架。关于自定义配置部分的所有答案都可以,但没有解决原始问题。
如果您需要实现自定义提供程序,例如MembershipProvider
,但是为了您自己的目的,您一定需要阅读这篇文章:
这是极好的读物。现在,如果您需要使用自己的属性扩展元素,那么您需要更改以下内容......
1)接下来是文章中讨论的代码(可能会有一些修改):
using System;
using System.Configuration;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration.Provider;
using System.Collections.Specialized;
public abstract class DataProvider : ProviderBase
{
// Define the methods to be used by the provider. These are custom methods to your own provider.
public abstract void Get();
public abstract void Delete();
}
public class DataProviderCollection : ProviderCollection { }
//The name is typically the same as the abstract class, minus the Provider part. Sticking to our (fake) example. we'd have a static class called Data.
public static class Data
{
private static bool _isInitialized = false;
private static DataProvider _provider;
public static DataProvider Provider
{
get
{
Initialize();
return _provider;
}
}
private static DataProviderCollection _providers;
public static DataProviderCollection Providers
{
get
{
Initialize();
return _providers;
}
}
private static void Initialize()
{
DataProviderConfigurationSection dataConfig = null;
if (!_isInitialized)
{
// get the configuration section for the feature
dataConfig = (DataProviderConfigurationSection)ConfigurationManager.GetSection("data");
if (dataConfig == null)
{
throw new ConfigurationErrorsException("Data is not configured to be used with this application");
}
_providers = new DataProviderCollection();
// use the ProvidersHelper class to call Initialize() on each provider
ProvidersHelper.InstantiateProviders(dataConfig.Providers, _providers, typeof(DataProvider));
// set a reference to the default provider
_provider = _providers[dataConfig.DefaultProvider] as DataProvider;
_isInitialized = true;
}
}
public static void Get()
{
Initialize();
if (_provider != null)
{
_provider.Get();
}
}
public static void Delete()
{
Initialize();
if (_provider != null)
{
_provider.Delete();
}
}
}
public class MyDataProvider : DataProvider
{
public override void Get()
{
// Get Code
}
public override void Delete()
{
// Delete Code
}
}
public class DataProviderConfigurationSection : ConfigurationSection
{
public DataProviderConfigurationSection()
{
_defaultProvider = new ConfigurationProperty("defaultProvider", typeof(string), null);
_providers = new ConfigurationProperty("providers", typeof(ProviderSettingsCollection), null);
_properties = new ConfigurationPropertyCollection();
_properties.Add(_providers);
_properties.Add(_defaultProvider);
}
private readonly ConfigurationProperty _defaultProvider;
[ConfigurationProperty("defaultProvider")]
public string DefaultProvider
{
get { return (string)base[_defaultProvider]; }
set { base[_defaultProvider] = value; }
}
private readonly ConfigurationProperty _providers;
[ConfigurationProperty("providers")]
public ProviderSettingsCollection Providers
{
get { return (ProviderSettingsCollection)base[_providers]; }
}
private ConfigurationPropertyCollection _properties;
protected override ConfigurationPropertyCollection Properties
{
get { return _properties; }
}
}
public static class ProvidersHelper
{
private static Type providerBaseType = typeof(ProviderBase);
/// <summary>
/// Instantiates the provider.
/// </summary>
/// <param name="providerSettings">The settings.</param>
/// <param name="providerType">Type of the provider to be instantiated.</param>
/// <returns></returns>
public static ProviderBase InstantiateProvider(ProviderSettings providerSettings, Type providerType)
{
ProviderBase base2 = null;
try
{
string str = (providerSettings.Type == null) ? null : providerSettings.Type.Trim();
if (string.IsNullOrEmpty(str))
{
throw new ArgumentException("Provider type name is invalid");
}
Type c = Type.GetType(str, true, true);
if (!providerType.IsAssignableFrom(c))
{
throw new ArgumentException(String.Format("Provider must implement type {0}.", providerType.ToString()));
}
base2 = (ProviderBase)Activator.CreateInstance(c);
NameValueCollection parameters = providerSettings.Parameters;
NameValueCollection config = new NameValueCollection(parameters.Count, StringComparer.Ordinal);
foreach (string str2 in parameters)
{
config[str2] = parameters[str2];
}
base2.Initialize(providerSettings.Name, config);
}
catch (Exception exception)
{
if (exception is ConfigurationException)
{
throw;
}
throw new ConfigurationErrorsException(exception.Message,
providerSettings.ElementInformation.Properties["type"].Source,
providerSettings.ElementInformation.Properties["type"].LineNumber);
}
return base2;
}
public static void InstantiateProviders(ProviderSettingsCollection providerSettings, ProviderCollection providers, Type type)
{
foreach (ProviderSettings settings in providerSettings)
{
providers.Add(ProvidersHelper.InstantiateProvider(settings, type));
}
}
}
2) 这是您用于上述代码的配置文件:
<configuration>
<configSections>
<section name="data" type="DataProviderConfigurationSection" />
</configSections>
<data defaultProvider="MyDataProvider">
<providers>
<add name="MydataProvider" type="MyDataProvider" />
</providers>
</data>
</configuration>
3)现在,您需要修改以下内容才能使用读取中的属性<add>
配置文件中的元素。
public abstract class DataProvider : ProviderBase
{
public string MyAttribute1 { get; set; }
public string MyAttribute2 { get; set; }
public string MyAttribute3 { get; set; }
// Define the methods to be used by the provider. These are custom methods to your own provider.
public abstract void Get();
public abstract void Delete();
public override void Initialize(string name, NameValueCollection config)
{
MyAttribute1 = config["MyAttribute1"];
MyAttribute2 = config["MyAttribute2"];
MyAttribute3 = config["MyAttribute3"];
base.Initialize(name, config);
}
}
4)配置文件如下所示:
<configuration>
<configSections>
<section name="data" type="DataProviderConfigurationSection" />
</configSections>
<data defaultProvider="MyDataProvider">
<providers>
<add name="MydataProvider" type="MyDataProvider" MyAttribute1="MyValue1" MyAttribute2="MyValue2" />
</providers>
</data>
</configuration>
作为奖励,这里有一个单元测试来验证它的工作原理:
[TestMethod]
public void RunMyDataProviderTest()
{
DataProvider dataProvider = Data.Provider;
Assert.IsInstanceOfType(dataProvider, typeof(MyDataProvider));
Assert.AreEqual(dataProvider.MyAttribute1, "MyValue1");
Assert.AreEqual(dataProvider.MyAttribute2, "MyValue2");
}