Setting DATA string on LayerObj in MapFile by Using Mapserver's PHP Mapscript

Question

I'm manipulating mapfiles through mapscript. Setting layer attribute values like the opacity works like this:

$layer = $map->getLayer('layername');
//set an attribute value
$layer->set('opacity', 80);

But now I want to set the data attribute as well, I assumed it functions like this:

$layer = $map->getLayer('layername');
//set an attribute value
$layer->set('data', '/path/to/my/shape/file.shp');

But nothing happens, i.e. an image is constructed but it's empty because no data was inserted.

How can I set the data string?

I'm using Mapserver 5.0.3 + Mapscript 4.10

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I used the map.getLayer() method instead of the getLayerByName method. While testing on the opacity attribute, I had a mapfile with only one layer, so the getLayer('loadlines') did return a (but in this case the last and correct) layer.

Answer 1

$layer = $map->getLayerByName('layername');
//set an attribute value
$layer->set('data', '/path/to/my/shape/file.shp');

or

$layer = $map->getLayer('layer_index'); //integer!
//set an attribute value
$layer->set('data', '/path/to/my/shape/file.shp');