App.config将嵌套组添加到现有节点

Question

我必须在根设置组中保存2组不同的设置.它应该是这样的:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>    
    <sectionGroup name="ROOT_GROUP">
       <sectionGroup name="GROUP_1">
         ........................
         some_settings
         ........................
       </sectionGroup>
       <sectionGroup name="GROUP_2">
         ........................
         some_other_settings
         ........................
       </sectionGroup>
     </sectionGroup>
  </configSections>
................................
other_system_tags
................................
</configuration>

Nuance是我必须在我的代码中的不同位置一个接一个地保存它.(例如,GROUP_1可以是连接字符串,GROUP_2是一些环境设置,它们一起由我的应用程序的不同部分中的用户填充)

我制作了这个简单的测试类来获得预期的结果

[TestFixture]
public class Tttt
{
    private string ROOT_GROUP = "ROOT_GROUP";
    private string GROUP_1 = "GROUP_1";
    private string GROUP_2 = "GROUP_2";

    [Test]
    public void SaveSettingsGroups()
    {
        SaveGroup1();
        SaveGroup2();
        Assert.True(true);
    }

    private Configuration GetConfig()
    {
        var configFilePath = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;
        var map = new ExeConfigurationFileMap { ExeConfigFilename = configFilePath };
        var config = ConfigurationManager.OpenMappedExeConfiguration(map, ConfigurationUserLevel.None);
        return config;
    }

    private void SaveGroup1()
    {
        var config = GetConfig();

        var root = new UserSettingsGroup();

        config.SectionGroups.Add(ROOT_GROUP, root);

        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(root.Name);

        var nested = new UserSettingsGroup();

        root.SectionGroups.Add(GROUP_1, nested);

        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(nested.Name);             
    }

    private void SaveGroup2()
    {
        var config = GetConfig();

        var root = config.GetSectionGroup(ROOT_GROUP);

        var nested = new UserSettingsGroup();
        root.SectionGroups.Add(GROUP_2, nested);

        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(nested.Name);
    }
}

但由于某种原因,此代码的结果是不同的

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>    
    <sectionGroup name="ROOT_GROUP">
      <sectionGroup name="GROUP_1">
        ........................
        some_settings
        ........................
      </sectionGroup>
    </sectionGroup>
    <sectionGroup name="ROOT_GROUP">
      <sectionGroup name="GROUP_2">
      ........................
      some_other_settings
      ........................
      </sectionGroup>
    </sectionGroup>
  </configSections>
................................
other_system_tags
................................
</configuration>

ROOT_GROUP节点是重复的,当然visual studio会抛出ROOT_GROUP已存在的异常.显然,当我将新的嵌套组添加到现有的根组然后保存它时,我的问题隐藏在方法SaveGroup2()中 - 但为什么呢？

UPD 我刚刚添加了新方法

    private void SaveGroup3()
    {
        var config = GetConfig();

        var root = config.GetSectionGroup(ROOT_GROUP);
        var nested1 = root.SectionGroups.Get(0);

        var nested2 = new UserSettingsGroup();
        var nested3 = new UserSettingsGroup();

        nested1.SectionGroups.Add("GROUP_2", nested2);
        root.SectionGroups.Add("GROUP_3", nested3);
        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(nested2.Name);
        ConfigurationManager.RefreshSection(nested3.Name);
    }

并在测试中替换它

[Test]
public void SaveSettingsGroups()
{
    SaveGroup1();
    SaveGroup3();
    Assert.True(true);
}

并得到了这种奇怪的行为

  <sectionGroup name="ROOT_GROUP">
    <sectionGroup name="GROUP_1">
      <sectionGroup name="GROUP_2">
      </sectionGroup>
    </sectionGroup>
    <sectionGroup name="GROUP_3">
    </sectionGroup>
  </sectionGroup>

正如你所看到的,奇怪的是结果完全是预期的.ROOT_GROUP没有重复,因为我需要它,但为什么它在SaveGroup2()中呢？我在SaveGroup2()中遗漏了什么吗？

UPD2 - HACK

刚试了一个简单的想法 - 如果我在添加一个新的嵌套元素之前清除root_group怎么办？

    private void SaveGroup2()
    {
        var config = GetConfig();

        var root = config.GetSectionGroup(ROOT_GROUP);

        var nested = new ConfigurationSectionGroup();

        //Copy exiting nested groups to array
        var gr = new ConfigurationSectionGroup[5];       
        root.SectionGroups.CopyTo(gr,0);
        gr[1] = nested;
        //<!----

        root.SectionGroups.Clear();

        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(root.Name);

        root.SectionGroups.Add(gr[0].Name, gr[0]);
        root.SectionGroups.Add(GROUP_2, gr[1]);

        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(root.Name);
    }

你怎么猜 - 它的作用!

<sectionGroup name="ROOT_GROUP">
  <sectionGroup name="GROUP_1" type="System.Configuration.UserSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
  </sectionGroup>
  <sectionGroup name="GROUP_2" type="System.Configuration.ConfigurationSectionGroup, System.Configuration, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" >
  </sectionGroup>
</sectionGroup>

我认为它看起来像一个bug或者有一些我错过的隐藏的东西.有人可以解释一下我做错了什么吗？

Answer 1

我花了一段时间才弄清楚发生了什么，在我看来，框架代码本身有问题，特别是class 内部的方法 。我不想写长篇大论，但如果您愿意，您可以调试 .Net 框架代码并亲自查看。WriteUnwrittenConfigDeclarationsRecursive(SectionUpdates declarationUpdates, XmlUtilWriter utilWriter, int linePosition, int indent, bool skipFirstIndent)MgmtConfigurationRecord

您可以通过以下方式修复代码：

1. 将所有组保存在一起

private void SaveGroups()
{
    var config = GetConfig();
    var root = new ConfigurationSectionGroup();
    config.SectionGroups.Add(ROOT_GROUP, root);
    config.Save(ConfigurationSaveMode.Modified);
    ConfigurationManager.RefreshSection(root.Name);

    var nested = new UserSettingsGroup();
    root.SectionGroups.Add(GROUP_1, nested);

    nested = new UserSettingsGroup(); 
    root.SectionGroups.Add(GROUP_2, nested);

    config.Save(ConfigurationSaveMode.Modified);
    ConfigurationManager.RefreshSection(root.Name);
}

2. 在添加新组项目之前删除现有组项目

private void SaveGroup2()
{
    var config = GetConfig();
    var root = config.SectionGroups[ROOT_GROUP];
    var existingGroups = new Dictionary<string, ConfigurationSectionGroup>();
    while (root.SectionGroups.Count > 0)
    {
        existingGroups.Add(root.SectionGroups.Keys[0], root.SectionGroups[0]);
        root.SectionGroups.RemoveAt(0);
    }

    config.Save(ConfigurationSaveMode.Modified);

    existingGroups.Add(GROUP_2, new UserSettingsGroup());
    foreach (var key in existingGroups.Keys)
    {
        existingGroups[key].ForceDeclaration(true);
        root.SectionGroups.Add(key, existingGroups[key]);
    }

    config.Save(ConfigurationSaveMode.Modified);
    ConfigurationManager.RefreshSection(root.Name);
}