将字符串转换为类名

I have a string variable that represents the name of a custom class. Example:

我有一个字符串变量，表示自定义类的名称。例：

string s = "Customer";

I will need to create an arraylist of customers. So, the syntax needed is:

我需要创建一个客户的arraylist。所以，所需的语法是：

List<Customer> cust = new ..

How do I convert the string s to be able to create this arraylist on runtime?

如何转换字符串s以便能够在运行时创建此arraylist？

2 个解决方案

#1

Well, for one thing ArrayList isn't generic... did you mean List<Customer>?

好吧，有一件事，ArrayList不是通用的...你的意思是List 吗？

You can use Type.GetType(string) to get the Type object associated with a type by its name. If the assembly isn't either mscorlib or the currently executing type, you'll need to include the assembly name. Either way you'll need the namespace too.

您可以使用Type.GetType（string）通过名称获取与类型关联的Type对象。如果程序集不是mscorlib或当前正在执行的类型，则需要包含程序集名称。无论哪种方式，您都需要命名空间。

Are you sure you really need a generic type? Generics mostly provide compile-time type safety, which clearly you won't have much of if you're finding the type at execution time. You may find it useful though...

你确定你真的需要通用类型吗？泛型主要提供编译时类型的安全性，如果你在执行时找到类型，那么显然你不会有太多的东西。你会发现它很有用......

Type elementType = Type.GetType("Customer");
Type listType = typeof(List<>).MakeGenericType(new Type[] { elementType });

object list = Activator.CreateInstance(listType);

If you need to do anything with that list, you may well need to do more generic reflection though... e.g. to call a generic method.

如果你需要对该列表做任何事情，你可能需要做更多的通用反思，例如...调用泛型方法。

#2

This is a reflection question. You need to find the type then instantiate an instance of it, something like this:

这是一个反思问题。您需要找到该类型然后实例化它的实例，如下所示：

Type hai = Type.GetType(classString,true);
Object o = (Activator.CreateInstance(hai));  //Or you could cast here if you already knew the type somehow

or, CreateInstance(assemblyName, className)

或者，CreateInstance（assemblyName，className）

You will need to watch out for namespace/type *es though, but that will do the trick for a simple scenario.

您需要注意命名空间/类型冲突，但这样做可以解决一个简单的场景。

Also, wrap that in a try/catch! Activator.CreateInstance is scary!

另外，将它包装在try / catch中！ Activator.CreateInstance很吓人！

#1