投对象泛型列表 [英] Cast Object to Generic List

问题描述

我有3个generict类型列表

I have 3 generict type list.

List<Contact> = new List<Contact>();
List<Address> = new List<Address>();
List<Document> = new List<Document>();

和保存与对象类型的变量。现在我做NEDD铸返回列表它进行一个foreach，有的像这样的：

And save it on a variable with type object. Now i nedd do Cast Back to List to perfom a foreach, some like this:

List<Contact> = (List<Contact>)obj;

但OBJ含量的变化每一次，我有一些这样的：

But obj content change every time, and i have some like this:

List<???> = (List<???>)obj;

我有另一个变量保持电流obj类型：

I have another variable holding current obj Type:

Type t = typeof(obj);

我可以做这样的事情的一些??：

Can i do some thing like that??:

List<t> = (List<t>)obj;

观测：我没有当前类型列表中，但我需要投，我现在另一个不的形式：

Obs: I no the current type in the list but i need to cast , and i dont now another form instead:

List<Contact> = new List<Contact>();

帮助PLZ !!!

Help Plz!!!

推荐答案

什么是棘手的问题。试试这个：

What a sticky problem. Try this:

List<Contact> c = null;
List<Address> a = null;
List<Document> d = null;

object o = GetObject();

c = o as List<Contact>;
a = o as List<Address>;
d = o as List<Document>;

℃之间，一个和d，有2零点和1个非空，或3空值。

Between c, a, and d, there's 2 nulls and 1 non-null, or 3 nulls.

以2：

object o = GetObject();
IEnumerable e = o as IEnumerable;
IEnumerable<Contact> c = e.OfType<Contact>();
IEnumerable<Address> a = e.OfType<Address>();
IEnumerable<Document> d = e.OfType<Document>();

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