c#動態型別，及動態物件的建立，合併2個物件，map
阿新 • • 發佈：2019-02-03
經常會遇到這樣的情況，我們在響應客戶端請求的資料的時候需要對資料進行處理，比如資料庫中的資料是int型，它可能表示某個列舉，或者其它的邏輯意義（資料庫這樣的設計可能是從資料安全性、儲存量上等角度考慮），但是客戶端顯示的時候需要是它具體的意義。這個時候我們的處理方式一般都是2中的，如果邏輯不復雜，且單一的話，直接修改sql語句就能處理好資料來源，這個時候程式碼裡面不需要處理什麼。但是如果邏輯復稍許複雜或者判斷的情況有很多分支，我們不得不從程式碼角度來處理了。單個物件還好，多個物件比如是個list<T>,那就要迴圈對某個物件的欄位進行XXX了。進而衍生出了這就出現了DTO，Arg的中間物件，當然，我個人是很喜歡這樣的設計的，但是某些時候也會偷懶不想寫（多半情況我直接寫程式碼生器批量生產），比如在測試的時候，在接私活的時候，在演示的時候，只為快速呈現想要的效果 都懶得去屑，是的，你會說市面上不是有很多的map庫，比如automap，tinymap，甚至json.net裡面的動態特性重寫，方法當然很多，但用一個大輪子來費力搞這麼個小事，我覺得划不來。且輪子越來越大它要乾的事越多，我可不想搞的那麼複雜，嗯，就是這樣，寫了個。具體的程式碼貼到下面，如果看明白，會很方便的擴充套件了或修改成自己想要的效果。
using System.Dynamic;
using System.Reflection;
using System.Collections.Concurrent;下面我們測試一個：private static readonly ConcurrentDictionary<RuntimeTypeHandle, PropertyInfo[]> DynamicObjectProperties = new ConcurrentDictionary<RuntimeTypeHandle, PropertyInfo[]>(); private IDictionary<string, Object> ToDynamicResult<T>(T classobj, Func<string, object, object> injectAct) where T : IInjectClass, new() { var type = typeof(T); var key = type.TypeHandle; var dynamicResult = new ExpandoObject() as IDictionary<string, Object>; PropertyInfo[] queryPts = null; DynamicObjectProperties.TryGetValue(key, out queryPts); if (queryPts == null) { queryPts = type.GetProperties(); DynamicObjectProperties.TryAdd(key, queryPts); } foreach (var p in queryPts) { var attributes = p.GetCustomAttributes(typeof(IngorePropertyAttribute), true); var columnMapping = attributes.FirstOrDefault(); if (columnMapping != null) continue; var _name = p.Name; var _value = p.GetValue(classobj, null); object _tempvalue = _value; if (injectAct != null) _tempvalue = injectAct.Invoke(_name, _value); //var value = Convert.ChangeType(value，typeof(string)); dynamicResult.Add(p.Name, _tempvalue); } return dynamicResult; } /// <summary> /// 支援動態輸出的物件介面 /// </summary> public interface IInjectClass { } /// <summary> /// 動態輸出時忽略此標記的屬性 /// </summary> public class IngorePropertyAttribute : Attribute { }
public class kk : IInjectClass
{
public string aa { get; set; }
public int bb { get; set; }
[IngoreProperty]
public bool cc { get; set; }
public DateTime dd { get; set; }
}kk ist = new kk(); ist.aa = "aaa"; ist.bb = 123; ist.cc = false; ist.dd = DateTime.Now; var tt = ToDynamicResult<kk>(ist, (k, v) => { if (k != "aa") return v; return v + "(改變了哦)"; }); var json = Tools.JsonUtils.JsonSerializer(tt); json = json + "<br /><br />" + Tools.JsonUtils.JsonSerializer(ToDynamicResult<kk>( new kk { aa = "test", bb = 789, cc = true, dd = DateTime.Now.AddDays(2) }, null)); Response.Write(json);
您可以重新構造帶引數的特性或者修改injectAct物件，改成適合自己的
下面寫個測試，改成表示式樹最好了，先上個碼
using System;
using System.Linq;
using System.Dynamic;
using System.Reflection;
using System.Linq.Expressions;
using System.Collections.Generic;
using System.Collections.Concurrent;
namespace Tools
{
public class Class2Map
{
private static readonly ConcurrentDictionary<RuntimeTypeHandle, PropertyInfo[]>
DynamicObjectProperties = new ConcurrentDictionary<RuntimeTypeHandle, PropertyInfo[]>();
private static PropertyInfo[] GetObjectProperties<T>()
{
var type = typeof(T);
var key = type.TypeHandle;
PropertyInfo[] queryPts = null;
DynamicObjectProperties.TryGetValue(key, out queryPts);
if (queryPts == null)
{
queryPts = type.GetProperties();
DynamicObjectProperties.TryAdd(key, queryPts);
}
return queryPts;
}
/// <summary>
/// 單個物件對映
/// </summary>
/// <typeparam name="T">型別</typeparam>
/// <param name="source">例項</param>
/// <param name="injectAct">map方法集</param>
/// <returns>對映後的動態物件</returns>
public static IDictionary<string, Object> DynamicResult<T>(T source, params MapCondition[] injectAct)//where T : ICustomMap
{
var queryPts = GetObjectProperties<T>();
var dynamicResult = new ExpandoObject() as IDictionary<string, Object>;
foreach (var p in queryPts)
{
var attributes = p.GetCustomAttributes(typeof(IngoreProperty), true);
if (attributes.FirstOrDefault() != null) continue;
var _name = p.Name; //原來是屬性名
var _value = p.GetValue(source, null); //原來的屬性值
object _resultvalue = _value; //最終的對映值
if (injectAct != null)
{
string _tempname = null;
var condition = injectAct.FirstOrDefault(x => x.Orginal == _name);
if (CheckChangeInfo(condition, out _tempname))
{
_resultvalue = condition.fn.Invoke(_value);
dynamicResult.Add(_tempname ?? _name, _resultvalue);
continue;
}
}
//var value = Convert.ChangeType(value，typeof(string));
dynamicResult.Add(_name, _resultvalue);
}
return dynamicResult;
}
/// <summary>
/// 合併2個物件
/// </summary>
/// <typeparam name="TSource">物件1型別</typeparam>
/// <typeparam name="TTarget">物件2型別</typeparam>
/// <param name="s">物件1例項</param>
/// <param name="t">物件2例項</param>
/// <returns>合併後的動態物件</returns>
public static IDictionary<string, Object> MergerObject<TSource, TTarget>(TSource s, TTarget t)
{
var targetPts = GetObjectProperties<TSource>();
PropertyInfo[] mergerPts = null;
var _type = t.GetType();
mergerPts = _type.Name.Contains("<>") ? _type.GetProperties() : GetObjectProperties<TTarget>();
var dynamicResult = new ExpandoObject() as IDictionary<string, Object>;
foreach (var p in targetPts)
{
var attributes = p.GetCustomAttributes(typeof(IngoreProperty), true);
if (attributes.FirstOrDefault() != null) continue;
dynamicResult.Add(p.Name, p.GetValue(s, null));
}
foreach (var p in mergerPts)
{
var attributes = p.GetCustomAttributes(typeof(IngoreProperty), true);
if (attributes.FirstOrDefault() != null) continue;
dynamicResult.Add(p.Name, p.GetValue(t, null));
}
return dynamicResult;
}
/// <summary>
/// 合併2個物件
/// </summary>
/// <typeparam name="TSource">物件1型別</typeparam>
/// <typeparam name="TTarget">物件2型別</typeparam>
/// <param name="s">物件1例項</param>
/// <param name="t">物件2例項</param>
/// <returns>合併後的動態物件</returns>
public static List<IDictionary<string, Object>> MergerListObject<TSource, TTarget>(List<TSource> s, TTarget t)
{
var targetPts = GetObjectProperties<TSource>();
PropertyInfo[] mergerPts = null;
var _type = t.GetType();
mergerPts = _type.Name.Contains("<>") ? _type.GetProperties() : GetObjectProperties<TTarget>();
var result = new List<IDictionary<string, Object>>();
s.ForEach(x =>
{
var dynamicResult = new ExpandoObject() as IDictionary<string, Object>;
foreach (var p in targetPts)
{
var attributes = p.GetCustomAttributes(typeof(IngoreProperty), true);
if (attributes.FirstOrDefault() != null) continue;
dynamicResult.Add(p.Name, p.GetValue(x, null));
}
foreach (var p in mergerPts)
{
var attributes = p.GetCustomAttributes(typeof(IngoreProperty), true);
if (attributes.FirstOrDefault() != null) continue;
dynamicResult.Add(p.Name, p.GetValue(t, null));
}
result.Add(dynamicResult);
});
return result;
}
private static bool CheckChangeInfo(MapCondition condition, out string name)
{
name = null;
bool result = condition != null &&
condition.fn != null &&
!string.IsNullOrWhiteSpace(condition.Orginal);//&&
//!string.IsNullOrWhiteSpace(condition.NewName);
if (result)
{
var temp = condition.NewName;
name = (string.IsNullOrWhiteSpace(temp) || temp.Trim().Length == 0) ? null : temp;
}
return result;
}
}
}List<KeyValue> kk = new List<KeyValue>
{
new KeyValue{key="aaa", value="111"},
new KeyValue{key="bbb", value="222"},
new KeyValue{key="ccc", value="333"},
new KeyValue{key="ddd", value="444"},
};
var result = Class2Map.MergerListObject<KeyValue, dynamic>(kk, new { p = "jon test" });
var json = JsonUtils.JsonSerializer(result);
Response.Write(json);[{"key":"aaa","value":"111","p":"jon test"},{"key":"bbb","value":"222","p":"jon test"},{"key":"ccc","value":"333","p":"jon test"},{"key":"ddd","value":"444","p":"jon test"}]var result = Class2Map.MergerObject<KeyValue, dynamic>(
new KeyValue { key = "aaa", value = "111" },
new { p = "jon test" }
);
var json = JsonUtils.JsonSerializer(result);
Response.Write(json);{ "key": "aaa", "value": "111", "p": "jon test" }