Selecting Entities in multiple layers

[dynamicscope]

ObjectARX 2007

Is it possible to select entities of multiple layers?

I've looked at...

http://through-the-interface.typepad.com/through_the_interface/2008/07/conditional-sel.html

...and tried the following code.

string[] layerNames = {"1", "2", "3"};
TypedValue[] tdv = new TypedValue[(layerNames.Length * 3) + 2];

int i = 0;
tdv[i++] = new TypedValue((int)DxfCode.Operator, "<or");
foreach (string ln in layerNames)
{
    tdv[i] = new TypedValue((int)DxfCode.Operator, "<and");
    tdv[i + 1] = new TypedValue((int)DxfCode.LayerName, ln);
    tdv[i + 2] = new TypedValue((int)DxfCode.Operator, "and>");
    i += 3;
}
tdv[i - 2] = new TypedValue((int)DxfCode.Operator, "or>");

SelectionFilter sf = new SelectionFilter(tdv);
PromptSelectionResult psr = ed.SelectAll(sf);

 This code gives me an error in the PromptSelectionResult.

What would cause the erro?

Or would there be a better way?

[Alexander.Rivilis · Accepted solution]

What about:

TypedValue((int)DxfCode.LayerName, "1,2,3");

?