Question

I need to execute a method "FindAll" in my page. This method returns a list of the object.

This is my method that I execute "FindAll". FindAll requires an int and returns an List of these class.

public void ObjectSource(int inicio, object o)
{
  Type tipo = o.GetType();
  object MyObj = Activator.CreateInstance(tipo);
  object[] args = new object[1];
  args[0] = inicio;
  List<object> list = new List<object>();
  object method = tipo.InvokeMember("FindAll", BindingFlags.Default | BindingFlags.InvokeMethod, null, null, args);
}

When I execute ObjectSource, it returns ok, but I can t access the result. In VS2008, I can visualize the list by "ctrl + Alt + q" but by casting doesn t work.

I forgot to say: this method "FindAll" is static!

Answer 1

Few things going on here, first, your method doesn t return the result.

Second, when you do return the object, there s nothing stopping you casting to the appropriate type in the calling code.

Third, you could use Generics to make this method strongly typed like so:

public T ObjectSource<T>(int inicio, T o)
{
  Type tipo = typeof(T);
  object MyObj = Activator.CreateInstance(tipo);
  object[] args = new object[1];
  args[0] = inicio;
  return tipo.InvokeMember("FindAll", BindingFlags.Default | BindingFlags.InvokeMethod, null, null, args) as T; 
}

Answer 2

Try this (updated):

public IEnumerable ObjectSource(int inicio, object o) {
    Type type = o.GetType();
    object[] args = new object[] { inicio };
    object result = type.InvokeMember("FindAll", 
        BindingFlags.Default | BindingFlags.InvokeMethod, null, o, args);
    return (IEnumerable) result;
}

A better solution would be to put your FindAll method into an interface -- say, IFindable, and make all your classes implement that interface. Then you can just cast the object to IFindable and call FindAll directly -- no reflection required.

Answer 3

Daniel, i got a few object that i need to bind a grid view and this list more than 1.000 records, then a want to pagging by 50, and this Object Source must be generic because will call FindAll of the classes!

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