"Description" value of layer

[pmorshed]

Hi. How can i get "description" property for a layer?! netDxf.Tables.Layer class doesn't contain the "Description"..

The "Description" field is very useful because special characters ( \<>/?":;*|,=` ) are allowed in it.

[haplokuon]

In the official DXF documentation there is no code for the layer description, but after checking if that value was really stored in the DXF, I found that it really does but in the extended data information. Another example of Autodesk at its best, they had to choose the worst way of saving a simple string. Why not do the same as the line type or the block which descriptions are saved under a code 3 and 4 respectively?

At the moment if you need the description you will have to read it manually from the XData.

[pmorshed]

Thanks How can i read it from XData? Do you have an example?

[haplokuon]

DxfDocument doc = DxfDocument.Load("Drawing1.dxf");
Layer layer = doc.Layers["Layer1"];
// Get the extended data information,
// how and where the layer description is stored is undocumented, proceed with care
// the layer description is saved as extended data information associated to an ApplicationRegistry called "AcAecLayerStandard"
string layerDescription;
XData xData = layer.XData["AcAecLayerStandard"];
foreach (XDataRecord data in xData.XDataRecord)
{
    // looks like it just stores two string values under a code 1000
    // the first one seems to be always empty, I do not know if it is there just to waste space
    // or it is actually used for something else from who knows where
    if (data.Code == XDataCode.String)
    {
        layerDescription = data.Value as string;
    }
}

If you need more detailed information about the extended data go to the AutoCad manual, you can start here.

[pmorshed]

Many thanks. You’re awesome