实现泛型设置类的最佳方式-反映Get/Set属性
本文关键字:Get 反映 Set 属性 方式 设置 泛型 最佳 实现 | 更新日期: 2023-09-27 17:53:31
我不知道如何制作通用设置类,希望您能帮助我。
首先,我想要一个单一的设置文件解决方案。为此,我创建了一个像这样的Singleton:
public sealed class Settings
{
private static readonly Lazy<Settings> _instance = new Lazy<Settings>(() => new Settings());
private Dictionary<string, object> m_lProperties = new Dictionary<string, object>();
public void Load(string fileName)
{
throw new NotImplementedException();
}
public void Save(string fileName)
{
throw new NotImplementedException();
}
public void Update()
{
throw new NotImplementedException();
}
/// <summary>
/// Gets the propery.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <returns></returns>
public string GetPropery(string propertyName)
{
return m_lProperties[propertyName].ToString() ?? String.Empty;
}
/// <summary>
/// Gets the propery.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <param name="defaultValue">The default value.</param>
/// <returns></returns>
public string GetPropery(string propertyName, string defaultValue)
{
if (m_lProperties.ContainsKey(propertyName))
{
return m_lProperties[propertyName].ToString();
}
else
{
SetProperty(propertyName, defaultValue);
return defaultValue;
}
}
/// <summary>
/// Sets the property.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <param name="value">The value.</param>
public void SetProperty(string propertyName, string value)
{
if (m_lProperties.ContainsKey(propertyName))
m_lProperties[propertyName] = value;
else
m_lProperties.Add(propertyName, value);
}
}
但我认为更好的方法是属性在类中,我可以通过反射获得属性。
-你能帮我实现这样的东西吗?
-是否有可能给属性属性像"加密=真"?在xml文件中保存/加载设置的最好方法是什么?
下面是一个如何使用实际设置的示例:
class Test()
{
private string applicationPath;
private string configurationPath;
private string configurationFile;
public Test()
{
applicationPath = Settings.Instance.GetPropery("ApplicationPath", AppDomain.CurrentDomain.BaseDirectory);
configurationPath = Settings.Instance.GetPropery("ConfigurationPath", "configurations");
configurationFile = Settings.Instance.GetPropery("ConfigurationFile", "application.xml");
// ... Load file with all settings from all classes
}
这是我自己的代码中相当相关的部分。
public class MyObject
{
public string StringProperty {get; set;}
public int IntProperty {get; set;}
public object this[string PropertyName]
{
get
{
return GetType().GetProperty(PropertyName).GetGetMethod().Invoke(this, null);
}
set
{
GetType().GetProperty(PropertyName).GetSetMethod().Invoke(this, new object[] {value});
}
}
}
它允许的是:
MyObject X = new MyObject();
//Set
X["StringProperty"] = "The Answer Is: ";
X["IntProperty"] = 42;
//Get - Please note that object is the return type, so casting is required
int thingy1 = Convert.ToInt32(X["IntProperty"]);
string thingy2 = X["StringProperty"].ToString();
更新:更多说明它的工作方式是反射式地访问属性,属性与字段的不同之处在于它们使用getter和setter,而不是直接声明和访问。您可以使用相同的方法来获取字段,或者也可以使用获取字段,如果您检查GetProperty的返回值为空,而不是简单地假设它有效。此外,正如在另一条评论中指出的那样,如果您使用不存在的属性原样调用它,这将中断,因为它缺乏任何形式的错误捕获。我以最简单的形式展示了代码,而不是最健壮的形式。
就属性属性而言....索引器需要在你想要使用它的类(或父类,我在我的BaseObject
上有它)中创建,所以在内部你可以在给定的属性上实现属性,然后在访问属性时应用开关或检查。也许让所有的属性一些其他自定义类,你实现Object Value; Bool Encrypted;
,然后在需要的时候从那里工作,它真的只是取决于你想要得到多少花式和你想写多少代码。
我不建议在可以不使用反射的地方使用反射,因为它非常慢。
我的例子没有反射和加密原型:
public sealed class Settings
{
private static readonly HashSet<string> _propertiesForEncrypt = new HashSet<string>(new string[] { "StringProperty", "Password" });
private static readonly Lazy<Settings> _instance = new Lazy<Settings>(() => new Settings());
private Dictionary<string, object> m_lProperties = new Dictionary<string, object>();
public void Load(string fileName)
{
// TODO: When you deserialize property which contains into "_propertiesForEncrypt" than Decrypt this property.
throw new NotImplementedException();
}
public void Save(string fileName)
{
// TODO: When you serialize property which contains into "_propertiesForEncrypt" than Encrypt this property.
throw new NotImplementedException();
}
public void Update()
{
throw new NotImplementedException();
}
/// <summary>
/// Gets the propery.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <returns></returns>
public object GetPropery(string propertyName)
{
if (m_lProperties.ContainsKey(propertyName))
return m_lProperties[propertyName];
return null;
}
/// <summary>
/// Gets the propery.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <param name="defaultValue">The default value.</param>
/// <returns></returns>
public object GetPropery(string propertyName, object defaultValue)
{
if (m_lProperties.ContainsKey(propertyName))
{
return m_lProperties[propertyName].ToString();
}
else
{
SetProperty(propertyName, defaultValue);
return defaultValue;
}
}
/// <summary>
/// Sets the property.
/// </summary>
/// <param name="propertyName">Name of the property.</param>
/// <param name="value">The value.</param>
public void SetProperty(string propertyName, object value)
{
if (m_lProperties.ContainsKey(propertyName))
m_lProperties[propertyName] = value;
else
m_lProperties.Add(propertyName, value);
}
// Sample of string property
public string StringProperty
{
get
{
return GetPropery("StringProperty") as string;
}
set
{
SetProperty("StringProperty", value);
}
}
// Sample of int property
public int IntProperty
{
get
{
object intValue = GetPropery("IntProperty");
if (intValue == null)
return 0; // Default value for this property.
return (int)intValue;
}
set
{
SetProperty("IntProperty", value);
}
}
}
使用像这样的动态类:https://gist.github.com/3914644这样您就可以访问您的属性:yourObject。stringProperty或youobject . intproperty
最大的问题之一是没有干净的方法将Object反序列化为Object。如果你事先不知道对象的类型,那就很难处理了。所以我们有一个替代的解决方案,存储类型信息。
如果没有列出,我将提供我认为是一个示例XML,以及使用它的方法,以及访问属性本身的方法。用于Get和Set属性的函数是正常的,不需要修改。
在单个类中,您需要确保该类中的相关属性在其自己的get/set方法中引用Settings类
public int? MyClassProperty
{
get
{
return (int?)Settings.Instance.GetProperty("MyClassProperty");
}
set
{
Settings.Instance.SetProperty("MyClassProperty", value);
}
}
在加载和保存函数中,您将需要使用序列化,特别是XmlSerializer
。为此,您需要适当地声明您的设置列表。为此,我将使用自定义类。
更新,允许正确加载
public class AppSetting
{
[XmlAttribute("Name")]
public string Name { get; set; }
[XmlAttribute("pType")]
public string pType{ get; set; }
[XmlIgnore()]
public object Value{ get; set; }
[XmlText()]
public string AttributeValue
{
get { return Value.ToString(); }
set {
//this is where you have to have a MESSY type switch
switch(pType)
{ case "System.String": Value = value; break;
//not showing the whole thing, you get the idea
}
}
}
那么,就不只是字典了,你会得到这样的东西:
public sealed class Settings
{
private static readonly Lazy<Settings> _instance = new Lazy<Settings>(() => new Settings());
private Dictionary<string, object> m_lProperties = new Dictionary<string, object>();
private List<AppSetting> mySettings = new List<AppSetting>();
你的加载函数将是一个简单的反序列化
public void Load(string fileName)
{//Note: the assumption is that the app settings XML will be defined BEFORE this is called, and be under the same name every time.
XmlSerializer ser = new XmlSerializer(typeof(List<AppSetting>));
FileStream fs = File.Open(fileName);
StreamReader sr = new StreamReader(fs);
mySettings = (List<AppSetting>)ser.DeSerialize(sr);
sr.Close();
fs.Close();
//skipping the foreach loop that will add all the properties to the dictionary
}
保存函数实际上需要反转它。
public void Save(string fileName)
{
//skipping the foreach loop that re-builds the List from the Dictionary
//Note: make sure when each AppSetting is created, you also set the pType field...use Value.GetType().ToString()
XmlSerializer ser = new XmlSerializer(typeof(List<AppSetting>));
FileStream fs = File.Open(fileName, FileMode.Create);
StreamWriter sw = new StreamWriter(fs);
//get rid of those pesky default namespaces
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
ns.Add("", "");
ser.Serialize(sw, mySettings, ns);
sw.Flush();
sw.Close();
fs.Close();
mySettings = null;//no need to keep it around
}
和XML应该像这样:
<ArrayOfAppSetting>
<AppSetting Name="ApplicationPath" pType="System.String">C:'Users'ME'Documents'Visual Studio 2010'Projects'WindowsFormsApplication1'WindowsFormsApplication1'bin'Debug'</AppSetting>
<AppSetting Name="ConfigurationPath" pType="System.String">configurations</AppSetting>
<AppSetting Name="ConfigurationFile" pType="System.String">application.xml</AppSetting>
<AppSetting Name="prop" pType="System.Int32">1</AppSetting>
</ArrayOfAppSetting>
我使用中间的List<>
来展示这个示例,因为事实证明您不能使用任何与XmlSerializer一起实现IDictionary的东西。它将初始化失败,它只是不起作用。
你可以在字典旁边创建和维护列表,也可以用list代替字典…确保您有检查来验证"Name"是唯一的,或者您可以简单地忽略列表,除非在Save和Load操作期间(这就是我编写这个例子的方式)
这实际上只适用于基本类型(int, double, string等),但由于您直接存储了该类型,因此您可以使用任何您想要的自定义类型,因为您知道它是什么以及如何处理它,因此您只需在AttributeValue
的set方法中处理它另一个更新:如果你只存储字符串,而不是所有类型的对象…它变得非常简单。去掉XmlIgnore value
和pType
,然后自动实现AttributeValue
。繁荣时期,完成了。这将限制您使用字符串和其他原语,但请确保其他类中的值的Get/Set适当地转换它们…但是它是一个更简单和容易的实现。