有没有一种优雅的快速方法将对象映射到字典,反之亦然?
示例:
IDictionary<string,object> a = new Dictionary<string,object>();
a["Id"]=1;
a["Name"]="Ahmad";
// .....
转变为
SomeClass b = new SomeClass();
b.Id=1;
b.Name="Ahmad";
// ..........
有没有一种优雅的快速方法将对象映射到字典,反之亦然?
IDictionary<string,object> a = new Dictionary<string,object>();
a["Id"]=1;
a["Name"]="Ahmad";
// .....
转变为
SomeClass b = new SomeClass();
b.Id=1;
b.Name="Ahmad";
// ..........
public static class ObjectExtensions
{
public static T ToObject<T>(this IDictionary<string, object> source)
where T : class, new()
{
var someObject = new T();
var someObjectType = someObject.GetType();
foreach (var item in source)
{
someObjectType
.GetProperty(item.Key)
.SetValue(someObject, item.Value, null);
}
return someObject;
}
public static IDictionary<string, object> AsDictionary(this object source, BindingFlags bindingAttr = BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance)
{
return source.GetType().GetProperties(bindingAttr).ToDictionary
(
propInfo => propInfo.Name,
propInfo => propInfo.GetValue(source, null)
);
}
}
class A
{
public string Prop1
{
get;
set;
}
public int Prop2
{
get;
set;
}
}
class Program
{
static void Main(string[] args)
{
Dictionary<string, object> dictionary = new Dictionary<string, object>();
dictionary.Add("Prop1", "hello world!");
dictionary.Add("Prop2", 3893);
A someObject = dictionary.ToObject<A>();
IDictionary<string, object> objectBackToDictionary = someObject.AsDictionary();
}
}
首先使用Newtonsoft将字典转换为JSON字符串。
var json = JsonConvert.SerializeObject(advancedSettingsDictionary, Newtonsoft.Json.Formatting.Indented);
然后将JSON字符串反序列化为您的对象
var myobject = JsonConvert.DeserializeObject<AOCAdvancedSettings>(json);
似乎只有反射可以在这里帮助..我已经做了一个将对象转换为字典和反之的小例子:
[TestMethod]
public void DictionaryTest()
{
var item = new SomeCLass { Id = "1", Name = "name1" };
IDictionary<string, object> dict = ObjectToDictionary<SomeCLass>(item);
var obj = ObjectFromDictionary<SomeCLass>(dict);
}
private T ObjectFromDictionary<T>(IDictionary<string, object> dict)
where T : class
{
Type type = typeof(T);
T result = (T)Activator.CreateInstance(type);
foreach (var item in dict)
{
type.GetProperty(item.Key).SetValue(result, item.Value, null);
}
return result;
}
private IDictionary<string, object> ObjectToDictionary<T>(T item)
where T: class
{
Type myObjectType = item.GetType();
IDictionary<string, object> dict = new Dictionary<string, object>();
var indexer = new object[0];
PropertyInfo[] properties = myObjectType.GetProperties();
foreach (var info in properties)
{
var value = info.GetValue(item, indexer);
dict.Add(info.Name, value);
}
return dict;
}
我强烈推荐使用Castle DictionaryAdapter,这是该项目中最好的保密之一。您只需定义一个带有所需属性的接口,然后在一行代码中,适配器将生成一个实现、实例化它,并将其值与传入的字典同步。我在 Web 项目中使用它来对我的 AppSettings 进行强类型管理:
var appSettings =
new DictionaryAdapterFactory().GetAdapter<IAppSettings>(ConfigurationManager.AppSettings);
请注意,我不需要创建实现IAppSettings接口的类 - 适配器会即时完成。此外,虽然在这种情况下我只是读取属性值,但理论上,如果我要在appSettings上设置属性值,适配器将使底层字典与这些更改保持同步。我认为您应该使用反射。类似于以下代码:
private T ConvertDictionaryTo<T>(IDictionary<string, object> dictionary) where T : new()
{
Type type = typeof (T);
T ret = new T();
foreach (var keyValue in dictionary)
{
type.GetProperty(keyValue.Key).SetValue(ret, keyValue.Value, null);
}
return ret;
}
它会取出你的字典并循环遍历来设置值。虽然有改进空间,但这是一个开始。你应该这样调用它:
SomeClass someClass = ConvertDictionaryTo<SomeClass>(a);
在Matías Fidemraizer的回答基础上,这里提供了一种支持绑定到除字符串以外的对象属性的版本。
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
namespace WebOpsApi.Shared.Helpers
{
public static class MappingExtension
{
public static T ToObject<T>(this IDictionary<string, object> source)
where T : class, new()
{
var someObject = new T();
var someObjectType = someObject.GetType();
foreach (var item in source)
{
var key = char.ToUpper(item.Key[0]) + item.Key.Substring(1);
var targetProperty = someObjectType.GetProperty(key);
//edited this line
if (targetProperty.PropertyType == item.Value.GetType())
{
targetProperty.SetValue(someObject, item.Value);
}
else
{
var parseMethod = targetProperty.PropertyType.GetMethod("TryParse",
BindingFlags.Public | BindingFlags.Static, null,
new[] {typeof (string), targetProperty.PropertyType.MakeByRefType()}, null);
if (parseMethod != null)
{
var parameters = new[] { item.Value, null };
var success = (bool)parseMethod.Invoke(null, parameters);
if (success)
{
targetProperty.SetValue(someObject, parameters[1]);
}
}
}
}
return someObject;
}
public static IDictionary<string, object> AsDictionary(this object source, BindingFlags bindingAttr = BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance)
{
return source.GetType().GetProperties(bindingAttr).ToDictionary
(
propInfo => propInfo.Name,
propInfo => propInfo.GetValue(source, null)
);
}
}
}
反射可以通过遍历属性将对象转换为字典。
要反过来做,你需要在C#中使用动态的ExpandoObject(实际上已经继承了IDictionary,因此已经为您完成了此操作),除非您可以从字典条目的集合中推断出类型。
因此,如果您处于.NET 4.0环境中,请使用ExpandoObject,否则您需要做很多工作...
public class SimpleObjectDictionaryMapper<TObject>
{
public static TObject GetObject(IDictionary<string, object> d)
{
PropertyInfo[] props = typeof(TObject).GetProperties();
TObject res = Activator.CreateInstance<TObject>();
for (int i = 0; i < props.Length; i++)
{
if (props[i].CanWrite && d.ContainsKey(props[i].Name))
{
props[i].SetValue(res, d[props[i].Name], null);
}
}
return res;
}
public static IDictionary<string, object> GetDictionary(TObject o)
{
IDictionary<string, object> res = new Dictionary<string, object>();
PropertyInfo[] props = typeof(TObject).GetProperties();
for (int i = 0; i < props.Length; i++)
{
if (props[i].CanRead)
{
res.Add(props[i].Name, props[i].GetValue(o, null));
}
}
return res;
}
}
public static RouteValueDictionary AnonymousObjectToHtmlAttributes(object htmlAttributes);
这是 System.Web.Mvc.HtmlHelper 类中的静态公共方法。
public Dictionary<string, object> ToDictionary<T>(string key, T value)
{
try
{
var payload = new Dictionary<string, object>
{
{ key, value }
};
} catch (Exception e)
{
return null;
}
}
public T FromDictionary<T>(Dictionary<string, object> payload, string key)
{
try
{
JObject jObject = (JObject) payload[key];
T t = jObject.ToObject<T>();
return (t);
}
catch(Exception e) {
return default(T);
}
}