如何动态加载单独的应用程序设置文件并与当前设置合并？

Question

有一些与从单独的配置文件中读取设置有关的问题和其他类似的问题它，但我的问题特定于应用程序属性设置（即 - 请参阅下面的 XML 文件）以及如何动态加载它们。我尝试了这篇文章中的方法，其中涉及刷新主配置文件的整个 appSettings 部分，但我的改编引发了异常，因为我没有替换 appSettings 部分：

var config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.PerUserRoamingAndLocal);
// Have tried the other ConfigurationUserLevels to no avail
config.AppSettings.File = myRuntimeConfigFilePath;
config.Save(ConfigurationSaveMode.Modified); // throws ConfigurationErrorsException
ConfigurationManager.RefreshSection("userSettings");

ConfigurationErrorsException.Message 是“根元素必须与引用文件“appSettings”的部分的名称匹配（C:\myFile.xml 第 2 行）。 ”该文件是：

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <userSettings>
        <MyApplication.Properties.Settings>
            <setting name="SineWaveFrequency" serializeAs="String">
                <value>6</value>
            </setting>
            <setting name="SineWaveAmplitude" serializeAs="String">
                <value>6</value>
            </setting>
        </MyApplication.Properties.Settings>
    </userSettings>
</configuration>

有没有办法将此文件中的值导入到 MyApplication.Properties.Settings.Default 类中，框架处理所有 XML 反序列化，就像加载配置文件时一样应用程序启动？

Answer 1

嗯，这是可行的：

using System;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Xml.Linq;
using System.Xml.XPath;

public static class SettingsIO
{
    internal static void Import(string settingsFilePath)
    {
        if (!File.Exists(settingsFilePath))
        {
            throw new FileNotFoundException();
        }

        var appSettings = Properties.Settings.Default;
        try
        {
            var config = 
ConfigurationManager.OpenExeConfiguration(
ConfigurationUserLevel.PerUserRoamingAndLocal);

            string appSettingsXmlName = 
Properties.Settings.Default.Context["GroupName"].ToString(); 
// returns "MyApplication.Properties.Settings";

            // Open settings file as XML
            var import = XDocument.Load(settingsFilePath);
            // Get the whole XML inside the settings node
            var settings = import.XPathSelectElements("//" + appSettingsXmlName);

            config.GetSectionGroup("userSettings")
                .Sections[appSettingsXmlName]
                .SectionInformation
                .SetRawXml(settings.Single().ToString());
            config.Save(ConfigurationSaveMode.Modified);
            ConfigurationManager.RefreshSection("userSettings");

            appSettings.Reload();
        }
        catch (Exception) // Should make this more specific
        {
            // Could not import settings.
            appSettings.Reload(); // from last set saved, not defaults
        }
    }

    internal static void Export(string settingsFilePath)
    {
        Properties.Settings.Default.Save();
        var config = 
ConfigurationManager.OpenExeConfiguration(
ConfigurationUserLevel.PerUserRoamingAndLocal);
        config.SaveAs(settingsFilePath);
    }
}

导出方法创建一个如下所示的文件：

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <userSettings>
        <MyApplication.Properties.Settings>
            <setting name="SineWaveFrequency" serializeAs="String">
                <value>1</value>
            </setting>
            <setting name="SineWaveAmplitude" serializeAs="String">
                <value>100</value>
            </setting>
            <setting name="AdcShift" serializeAs="String">
                <value>8</value>
            </setting>
            <setting name="ControlBitsCheckedIndices" serializeAs="String">
                <value>0,1,2,3,5,6,7,8</value>
            </setting>
            <setting name="UpgradeSettings" serializeAs="String">
                <value>False</value>
            </setting>
        </MyApplication.Properties.Settings>
    </userSettings>
</configuration>

导入方法解析该文件，获取节点内的所有内容，将该 XML 放入 user.config 文件的适当部分，然后重新加载 Properties.Settings。默认是为了从新的 user.config 文件中获取这些值。

Answer 2

Pat建议的解决方案：

// Get the whole XML inside the settings node
var settings = import.XPathSelectElements("//" + appSettingsXmlName);

返回null。我将其更改为

var settings = import.Element("configuration").Element("userSettings").Element(appSettingsXmlName);

config.GetSectionGroup("userSettings")
      .Sections[appSettingsXmlName]
      .SectionInformation
      .SetRawXml(settings.ToString());

并且效果完美。