问题
My problem: I have an assembly in 2 versions and want to use them at the same time in my Python project.
The .NET libs are installed in GAC (MSIL), having the same public token:
lib.dll (1.0.0.0)
lib.dll (2.0.0.0)
In Python I want something like that:
import clr
clr.AddReference("lib, Version=1.0.0.0, ...")
from lib import Class
myClass1 = Class()
myClass1.Operation()
*magic*
clr.AddReference("lib, Version=2.0.0.0, ...")
from lib import class
myClass2 = Class()
myClass2.Operation()
myClass2.OperationFromVersion2()
*other stuff*
# both objects should be accessibly
myClass1.Operation()
myClass2.OperationFromVersion2()
Is there a way to do that? Something with AppDomains or bindingRedirect?
Note: Of course myClass1.operationFromVersion2() can fail...
回答1:
Well I found a solution: Python for .NET also supports Reflection!
Instead of
clr.AddReference("lib, Version=1.0.0.0, ...")
You have to use
assembly1 = clr.AddReference("lib, Version=1.0.0.0, ...")
With that assembly you can use all the Reflection stuff like in C#. In my example I have to use following code (same for version 2):
from System import Type
type1 = assembly1.GetType(...)
constructor1 = type1.GetConstructor(Type.EmptyTypes)
myClass1 = constructor1.Invoke([])
回答2:
I could not get it working using the accepted answer. Here is my solution.
Instead of using PythonNet you must use the .NET framework directly:
import System
dll_ref = System.Reflection.Assembly.LoadFile(fullPath)
print(dll_ref.FullName)
print(dll_ref.Location)
Check that the correct DLL is used.
To use multiple DLLs with the same version just load it to another variable
another_dll_ref = System.Reflection.Assembly.LoadFile(anotherFullPath)
Now you can use objects from the specified dll.
Instance of a public non-static class
some_class_type = dll_ref.GetType('MyNamespace.SomeClass')
my_instance = System.Activator.CreateInstance(some_class_type)
my_instance.a = 4 # setting attribute
my_instance.b('whatever') # calling methods
Calling a method in a public static class
some_class_type = dll_ref.GetType('MyNamespace.SomeClass')
method = some_class_type.GetMethod('SomeMethod')
# return type and list of parameters
method.Invoke(None, [1, 2.0, '3'])
Creating a instance of a struct
some_struct_type = dll_ref.GetType('MyNamespace.SomeStruct')
my_struct = System.Activator.CreateInstance(some_struct_type)
my_struct.a = 3
(taken from my question Python for .NET: How to explicitly create instances of C# classes using different versions of the same DLL?)
来源：https://stackoverflow.com/questions/31408391/python-for-net-using-same-net-assembly-in-multiple-versions