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动态库只包含元数据,不包含类型

typebuilder .net-assembly dll dynamic c#

Thomas Flinkow · 技术社区 · 7 年前

使用.NET4.7.2,我动态地生成 .dll

internal class Program
{
    private static void Main(string[] args)
    {
        AssemblyBuilder assemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(new AssemblyName("MyAssembly"), AssemblyBuilderAccess.RunAndSave);
        ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("ModuleName");
        TypeBuilder typeBuilder = moduleBuilder.DefineType("MyNamespace.TypeName", TypeAttributes.Public);

        typeBuilder.DefineDefaultConstructor(MethodAttributes.Public);

        // Build the method 'public int ReturnTheAnswer() => 42;'.
        MethodBuilder newMethod = typeBuilder.DefineMethod("ReturnTheAnswer", MethodAttributes.Public, typeof(int), new Type[0]);
        ILGenerator ilGen = newMethod.GetILGenerator();
        ilGen.Emit(OpCodes.Ldc_I4_S, 42);
        ilGen.Emit(OpCodes.Ret);

        Type newType = typeBuilder.CreateType();

        assemblyBuilder.Save("MyAssembly.dll"); // Save the assembly in the programs work directory ('bin\Debug').

        dynamic o = Activator.CreateInstance(newType); // Create an instance of the dynamically created type.
        int r = (int) o.ReturnTheAnswer();

        Debug.Assert(r == 42); // If this doesn't fail, the type has been built correctly, is in fact in the .dll and can be used perfectly fine.
    }
}

我可以用 .dll文件 .dll文件 对于DotPeek和ilspy,它们都不显示任何名称空间或类型(尽管它们应该显示类型) TypeName 在命名空间中 MyNamespace

为什么在使用两个不同的反编译器时程序集看起来是空的,但是从代码中使用它的类型却可以很好地工作?

1 回复 | 直到 7 年前

pfx 7 年前

无法保存您的类型,因为它是在 .
AssemblyBuilder 的 Save
看到了吗 remarks .

此方法保存此方法中定义的所有非瞬态动态模块
不保存瞬态动态模块。
程序集文件名可以与其中一个模块的名称相同。如果是,大会清单存储在该模块中。assemblyFileName可以是与中包含的所有模块的名称不同装配。如果是,则程序集文件仅包含程序集

要持久化您的类型,您必须以非暂时形式声明它 持久动态模块 ,使用 DefineDynamicModule fileName 论点,像这样:

ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("ModuleName", "MyAssembly.dll");

您的完整代码如下所示。

AssemblyBuilder assemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(new 
AssemblyName("MyAssembly"), AssemblyBuilderAccess.RunAndSave);
ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("ModuleName", "MyAssembly.dll");
TypeBuilder typeBuilder = moduleBuilder.DefineType("MyNamespace.TypeName", TypeAttributes.Public);

typeBuilder.DefineDefaultConstructor(MethodAttributes.Public);

// Build the method 'public int ReturnTheAnswer() => 42;'.
MethodBuilder newMethod = typeBuilder.DefineMethod("ReturnTheAnswer", 
MethodAttributes.Public, typeof(int), new Type[0]);
ILGenerator ilGen = newMethod.GetILGenerator();
ilGen.Emit(OpCodes.Ldc_I4_S, 42);
ilGen.Emit(OpCodes.Ret);

Type newType = typeBuilder.CreateType();

assemblyBuilder.Save("MyAssembly.dll"); // Save the assembly in the programs work directory ('bin\Debug').

dynamic o = Activator.CreateInstance(newType); // Create an instance of the dynamically created type.
int r = (int) o.ReturnTheAnswer();

Debug.Assert(r == 42); // If this doesn't fail, the type has been built correctly, is in fact in the .dll and can be used perfectly fine.