dll - Load a class dynamically in C# -

i trying load class (say class1:interface ) without knowing name assembly. code looks this:

assembly = assembly.loadfrom("mydll.dll"); type t = (type)a.gettypes()[0]; (interface) classinstance = (interface) (clasactivator.createinstance(t); 

based on articles found online , msdn, gettypes()[0] suppose return class1 (there 1 class in mydll.dll). however, code returns class1.properties.settings. line 3 creates exception:

unable cast object of type 'class1.properties.settings' type namespace.interface'. 

i not know why , how fix problem.

the assembly can hold more 1 type (you have settings.settings file in dll, creates class under hood in settings.designer.cs file), first class in code in case turned out settings class, need go through types , search ones have interface need.

assembly asm = assembly.loadfrom("mydll.dll"); type[] alltypes = asm.gettypes(); foreach (type type in alltypes) {     // scan objects not abstract , implements interface     if (!type.isabstract && typeof(imyinterface).isassignablefrom(type));     {         // create instance of class...         var inst = (imyinterface)activator.createinstance(type);          //do work here, may called more once if more 1 class implements imyinterface     } }