我有一个通用字典dictionary <string, T>,我想基本上使克隆()..任何建议。
当前回答
这对我来说很好
// assuming this fills the List
List<Dictionary<string, string>> obj = this.getData();
List<Dictionary<string, string>> objCopy = new List<Dictionary<string, string>>(obj);
正如Tomer Wolberg在评论中所描述的,如果值类型是可变类,这是行不通的。
其他回答
我将计算T是否为值或引用类型。如果T是值类型,我将使用Dictionary的构造函数,如果T是引用类型,我将确保T继承自ICloneable。
它会给
private static IDictionary<string, T> Copy<T>(this IDictionary<string, T> dict)
where T : ICloneable
{
if (typeof(T).IsValueType)
{
return new Dictionary<string, T>(dict);
}
else
{
var copy = new Dictionary<string, T>();
foreach (var pair in dict)
{
copy[pair.Key] = pair.Value;
}
return copy;
}
}
这里是克隆字典的另一种方法,假设你知道做“正确”的事情,只要处理任何隐藏在“T”(a.k.a)后面的东西。“对象”)。
internal static Dictionary<string, object> Clone(Dictionary<string, object> dictIn)
{
Dictionary<string, object> dictOut = new Dictionary<string, object>();
IDictionaryEnumerator enumMyDictionary = dictIn.GetEnumerator();
while (enumMyDictionary.MoveNext())
{
string strKey = (string)enumMyDictionary.Key;
object oValue = enumMyDictionary.Value;
dictOut.Add(strKey, oValue);
}
return dictOut;
}
这里是一些真正的“真正的深度复制”,不知道类型用一些递归行走,很适合初学者。我认为它适用于嵌套类型和几乎所有棘手的类型。我还没有添加嵌套数组处理,但是您可以根据自己的选择进行修改。
Dictionary<string, Dictionary<string, dynamic>> buildInfoDict =
new Dictionary<string, Dictionary<string, dynamic>>()
{
{"tag",new Dictionary<string,dynamic>(){
{ "attrName", "tag" },
{ "isCss", "False" },
{ "turnedOn","True" },
{ "tag",null }
} },
{"id",new Dictionary<string,dynamic>(){
{ "attrName", "id" },
{ "isCss", "False" },
{ "turnedOn","True" },
{ "id",null }
} },
{"width",new Dictionary<string,dynamic>(){
{ "attrName", "width" },
{ "isCss", "True" },
{ "turnedOn","True" },
{ "width","20%" }
} },
{"height",new Dictionary<string,dynamic>(){
{ "attrName", "height" },
{ "isCss", "True" },
{ "turnedOn","True" },
{ "height","20%" }
} },
{"text",new Dictionary<string,dynamic>(){
{ "attrName", null },
{ "isCss", "False" },
{ "turnedOn","True" },
{ "text","" }
} },
{"href",new Dictionary<string,dynamic>(){
{ "attrName", null },
{ "isCss", "False" },
{ "flags", "removeAttrIfTurnedOff" },
{ "turnedOn","True" },
{ "href","about:blank" }
} }
};
var cln=clone(buildInfoDict);
public static dynamic clone(dynamic obj)
{
dynamic cloneObj = null;
if (IsAssignableFrom(obj, typeof(IDictionary)))
{
cloneObj = Activator.CreateInstance(obj.GetType());
foreach (var key in obj.Keys)
{
cloneObj[key] = clone(obj[key]);
}
}
else if (IsNumber(obj) || obj.GetType() == typeof(string))
{
cloneObj = obj;
}
else
{
Debugger.Break();
}
return cloneObj;
}
public static bool IsAssignableFrom(this object obj, Type ObjType = null, Type ListType = null, bool HandleBaseTypes = false)
{
if (ObjType == null)
{
ObjType = obj.GetType();
}
bool Res;
do
{
Res = (ObjType.IsGenericType && ObjType.GetGenericTypeDefinition().IsAssignableFrom(ListType)) ||
(ListType == null && ObjType.IsAssignableFrom(obj.GetType()));
ObjType = ObjType.BaseType;
} while ((!Res && ObjType != null) && HandleBaseTypes && ObjType != typeof(object));
return Res;
}
public static bool IsNumber(this object value)
{
return value is sbyte
|| value is byte
|| value is short
|| value is ushort
|| value is int
|| value is uint
|| value is long
|| value is ulong
|| value is float
|| value is double
|| value is decimal;
}
对我来说最好的方法是:
Dictionary<int, int> copy= new Dictionary<int, int>(yourListOrDictionary);
对于。net 2.0,你可以实现一个继承自Dictionary并实现ICloneable的类。
public class CloneableDictionary<TKey, TValue> : Dictionary<TKey, TValue> where TValue : ICloneable
{
public IDictionary<TKey, TValue> Clone()
{
CloneableDictionary<TKey, TValue> clone = new CloneableDictionary<TKey, TValue>();
foreach (KeyValuePair<TKey, TValue> pair in this)
{
clone.Add(pair.Key, (TValue)pair.Value.Clone());
}
return clone;
}
}
然后,只需调用clone方法就可以克隆字典。当然,这个实现要求字典的值类型实现ICloneable,但除此之外,泛型实现根本不实用。
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