在.NET .config文件中读取和写入值

时间:2012-05-05 21:22:10

标签: c# .net configuration configuration-files configurationmanager

我想为user.config文件使用自定义路径,而不是让.NET从默认位置读取它。

我打开这样的文件:

ExeConfigurationFileMap configMap = new ExeConfigurationFileMap();
configMap.ExeConfigFilename = String.Format("{0}\\user.config",AppDataPath);
Configuration config = ConfigurationManager.OpenMappedExeConfiguration(configMap, ConfigurationUserLevel.PerUserRoamingAndLocal);

但是我无法弄清楚如何实际读取它的设置,我得到一个编译错误,说当我尝试通过AppData或ConfigurationSection获取值时,这些值是不可访问的。

我是否需要创建某种包装类来正确使用数据?

3 个答案:

答案 0 :(得分:2)

我最近遇到了类似的问题,我不得不将设置文件的位置从AppData中的默认位置更改为Application目录。我的解决方案是创建自己的设置文件,该文件派生自指定自定义ApplicationSettingsBaseSettingsProvider。虽然解决方案起初感觉有些过分,但我发现它比我预期的更灵活和可维护。

<强>更新

示例设置文件:

public class BaseSettings : ApplicationSettingsBase
{
    protected BaseSettings(string settingsKey)
       { SettingsKey = settingsKey.ToLower(); }


    public override void Upgrade()
    {
         if (!UpgradeRequired)
             return;
         base.Upgrade();
         UpgradeRequired = false;
         Save();
    }


    [SettingsProvider(typeof(MySettingsProvider)), UserScopedSetting]
    [DefaultSettingValue("True")]
    public bool UpgradeRequired
    {
         get { return (bool)this["UpgradeRequired"]; }
         set { this["UpgradeRequired"] = value; }
    }
}

Sample SettingsProvider:

public sealed class MySettingsProvider : SettingsProvider
{
    public override string ApplicationName { get { return Application.ProductName; } set { } }
    public override string Name { get { return "MySettingsProvider"; } }


    public override void Initialize(string name, NameValueCollection col)
         { base.Initialize(ApplicationName, col); }


    public override void SetPropertyValues(SettingsContext context, SettingsPropertyValueCollection propertyValues)
    {
       // Use an XmlWriter to write settings to file. Iterate PropertyValueCollection and use the SerializedValue member
    }


    public override SettingsPropertyValueCollection GetPropertyValues(SettingsContext context, SettingsPropertyCollection props)
    {
       // Read values from settings file into a PropertyValuesCollection and return it
    }


    static MySettingsProvider()
    {
        appSettingsPath_ = Path.Combine(new FileInfo(Application.ExecutablePath).DirectoryName, settingsFileName_);

        settingsXml_ = new XmlDocument();
        try { settingsXml_.Load(appSettingsPath_); }
        catch (XmlException) { CreateXmlFile_(settingsXml_); } //Invalid settings file
        catch (FileNotFoundException) { CreateXmlFile_(settingsXml_); } // Missing settings file
    }
}

答案 1 :(得分:1)

一些改进:

1)加载起来更简单,不需要其他行:

var config = ConfigurationManager.OpenExeConfiguration(...);

2)正确访问AppSettings

config.AppSettings.Settings[...]; // and other things under AppSettings

3)如果您需要自定义配置部分,请使用此工具:http://csd.codeplex.com/

答案 2 :(得分:0)

我从未最终使配置管理器方法正常工作。在花了半天糊涂没有进展之后,我决定推出自己的解决方案,因为我的需求是基本的。

这是我最终提出的解决方案:

public class Settings
{
    private XmlDocument _xmlDoc;
    private XmlNode _settingsNode;
    private string _path;

    public Settings(string path)
    {
        _path = path;
        LoadConfig(path);
    }

    private void LoadConfig(string path)
    {
       //TODO: add error handling
        _xmlDoc = null;
        _xmlDoc = new XmlDocument();
        _xmlDoc.Load(path);
        _settingsNode = _xmlDoc.SelectSingleNode("//appSettings");
    }

    //
    //use the same structure as in .config appSettings sections
    //
    public string this[string s]
    {
        get
        {
            XmlNode n = _settingsNode.SelectSingleNode(String.Format("//add[@key='{0}']", s));
            return n != null ? n.Attributes["value"].Value : null;
        }
        set
        {
            XmlNode n = _settingsNode.SelectSingleNode(String.Format("//add[@key='{0}']", s));

            //create the node if it doesn't exist
            if (n == null)
            {
                n=_xmlDoc.CreateElement("add");
                _settingsNode.AppendChild(n);
                XmlAttribute attr =_xmlDoc.CreateAttribute("key");
                attr.Value = s;
                n.Attributes.Append(attr);
                attr = _xmlDoc.CreateAttribute("value");
                n.Attributes.Append(attr);
            }

            n.Attributes["value"].Value = value;
            _xmlDoc.Save(_path);
        }
    }
}