自定义App.config NameValueSectionHandler的bug修复创建自己的NameValueCollectionSectionHandler

在很多时候我们需要自定义我们自己的自定义App.config 文件，而微软为我们提供了默认的

      System.Configuration.NameValueSectionHandler

      System.Configuration.DictionarySectionHandler

      System.Configuration.SingleTagSectionHandler

经常用这些也没有出现问题。今天因项目需求的问题再次使用System.Configuration.NameValueSectionHandler，相应的配置如下：

<configSections>
<section name="mySection1" type="System.Configuration.NameValueSectionHandler, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>
</configSections>
<mySection1>
<add key="filepath" value="Views/Channel/men"></add>
<add key="filepath" value="Views/Channel/homme"></add>
<add key="filepath" value="Views/Channel/fleece/20120906"></add>
<add key="filepath" value="Views/Channel/Designer"></add>
<add key="filepath" value="Views/Channel/coats/20120816"></add>
<add key="filepath" value="Views/Channel/xiuxianku/20120517"></add>
<add key="filepath" value="men"></add>
<add key="filepath" value="homme"></add>
<add key="filepath" value="fleece"></add>
<add key="filepath" value="Designer"></add>
<add key="filepath" value="coats"></add>
<add key="filepath" value="xiuxianku"></add>
</mySection1>
然后在读取相应的配置信息。

   NameValueCollection mySection1 = ((NameValueCollection)ConfigurationManager.GetSection("mySection1"));
List<string> fileList = mySection1["filepath"].Split(new char[] { ',' }).ToList();得到的结果只有最后一条，而我们所用的NameValueCollection不一致，让我们来看看源码吧：

internal static object CreateStatic(object parent, XmlNode section, string keyAttriuteName, string valueAttributeName)
{
ReadOnlyNameValueCollection values;
if (parent == null)
{
values = new ReadOnlyNameValueCollection(StringComparer.OrdinalIgnoreCase);
}
else
{
ReadOnlyNameValueCollection values2 = (ReadOnlyNameValueCollection) parent;
values = new ReadOnlyNameValueCollection(values2);
}
HandlerBase.CheckForUnrecognizedAttributes(section);
foreach (XmlNode node in section.ChildNodes)
{
if (!HandlerBase.IsIgnorableAlsoCheckForNonElement(node))
{
if (node.Name == "add")
{
string str = HandlerBase.RemoveRequiredAttribute(node, keyAttriuteName);
string str2 = HandlerBase.RemoveRequiredAttribute(node, valueAttributeName, true);
HandlerBase.CheckForUnrecognizedAttributes(node);
values[str] = str2;
}
else if (node.Name == "remove")
{
string name = HandlerBase.RemoveRequiredAttribute(node, keyAttriuteName);
HandlerBase.CheckForUnrecognizedAttributes(node);
values.Remove(name);
}
else if (node.Name.Equals("clear"))
{
HandlerBase.CheckForUnrecognizedAttributes(node);
values.Clear();
}
else
{
HandlerBase.ThrowUnrecognizedElement(node);
}
}
}
values.SetReadOnly();
return values;
}

很明显在add的时候它用的是values[str]
= str2;而不是调用add方法。
修改后代码：

public class NameValueCollectionSectionHandler : IConfigurationSectionHandler
{
// Fields
private const string defaultKeyAttribute = "key";
private const string defaultValueAttribute = "value";

// Methods
public object Create(object parent, object context, XmlNode section)
{
return CreateStatic(parent, section, this.KeyAttributeName, this.ValueAttributeName);
}

internal static object CreateStatic(object parent, XmlNode section)
{
return CreateStatic(parent, section, "key", "value");
}

internal static object CreateStatic(object parent, XmlNode section, string keyAttriuteName, string valueAttributeName)
{
NameValueCollection values;
if (parent == null)
{
values = new NameValueCollection(StringComparer.OrdinalIgnoreCase);
}
else
{
NameValueCollection values2 = (NameValueCollection)parent;
values = new NameValueCollection(values2);
}

foreach (XmlNode node in section.ChildNodes)
{
if (node.Name == "add")
{
string key = node.Attributes[keyAttriuteName].Value;
string value = node.Attributes[valueAttributeName].Value;
values.Add(key, value);
}
else if (node.Name == "remove")
{
string key = node.Attributes[keyAttriuteName].Value;
values.Remove(key);
}
else if (node.Name.Equals("clear"))
{
values.Clear();
}
}
return values;
}

// Properties
protected virtual string KeyAttributeName
{
get
{
return "key";
}
}

protected virtual string ValueAttributeName
{
get
{
return "value";
}
}
}

当然这样运行结果就和我们常用的NameValueCollection一样。