具有“反射”参数的C＃中的InvokeMember

Question

I want to call a method of a DLL via reflection (can't be sure that the other dll is loaded) but have problems with the parameters.

The method I want to call is

public void Add(DBTable table, String sField, DBValue value, SQLConditionType type)

in the MP-TVSeries project

What I tried is this:

        // WindowPlugins.GUITVSeries
        Assembly MPTVSeries = Assembly.Load("MP-TVSeries");
        Type sqlConditionType = MPTVSeries.GetType("WindowPlugins.GUITVSeries.SQLCondition");
        Type sqlConditionTypeEnumType = MPTVSeries.GetType("WindowPlugins.GUITVSeries.SQLConditionType");
        Type dbEpisode = MPTVSeries.GetType("WindowPlugins.GUITVSeries.DBEpisode");

        // SQLCondition sql = new SQLCondition();
        object sql = Activator.CreateInstance(sqlConditionType);

        // sql.Add(new DBEpisode(), DBEpisode.cFilename, filename, SQLConditionType.Equal);
        sqlConditionType.InvokeMember("Add",
        BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.Public,
        null,
        sql,
        new object[] { 
            Activator.CreateInstance(dbEpisode),
            dbEpisode.GetField("cFilename"),
            filename,
            sqlConditionTypeEnumType.GetField("Equal")
        });

but this throws an exception with the message

The method "WindowPlugins.GUITVSeries.SQLCondition.Add" could not be found.

My guess is that I am doing something wrong with the parameters, but as I am totally new to reflection I can't get my head around it.

Someone please help ;-)

Answer 1

You are going too fast. Get sqlConditionType.GetMethod() working first to get a MethodInfo so you can be sure this is not a method overload resolution problem. The arguments you pass are smelly, particularly filename and sqlConditionTypeEnumType.GetField("Equal") .