Adding layers to a map document

There will be many situations where you will need to add a layer to a map document. The mapping module provides this functionality through the AddLayer() function. In this recipe, you will learn how to add a layer to a map document using this function.

Getting ready

arcpy.mapping provides the ability to add layers or group layers into an existing map document file. You can take advantage of the ArcMap "auto-arrange" functionality, which automatically places a layer in the data frame for visibility. This is essentially the same functionality provided by the Add Data button in ArcMap, which positions a layer in the data frame based on geometry type and layer weight rules.

Note

Layers can't be added to a layer file (.lyr).

When adding a layer to a map document, the layer must reference an existing layer found in a layer file on disk, the same map document and data frame, the same map document with a different data frame, or a completely separate map document. A...