Constructing file path within Python for Feature Class within Feature Dataset?

Question

Based on my understanding of the ArcGIS path structure, a feature class inside a feature dataset inside a geodatabase can be accessed by the following:

C:\Menu\Lunch.gdb\Sandwich\Cheese

Where Sandwich is the feature dataset and Cheese is the feature class.

In a python script, I want to construct this full path, so that I can check it using arcpy.Exists(x). I have the following variables (pseudocode):

WSpace = C:\Menu\Lunch.gdb\
FDSName = Sandwich
FCName = Cheese

Concatenating WSpace and FDSName gives the correct path to the feature dataset. What I need help with is tacking FCName onto the end. I would think the following code would work, but it renders a space instead of the backslash character:

fullPath = WSpace + FDSName + r"\" + FCName

Instead of r"\", I have also tried "\\", and "/", but they all render a space. This seems like a simple syntax problem.

Answer 1

Strings, even when marked as r"Raw strings", cannot end with a slash, it needs to be escaped. Should be:

fullPath = WSpace + FDSName + "\\" + FCName

Or better yet, use os.path.join:

fullPath = os.path.join(WSpace, FDSName, FCName)

Answer 2

I don't know why, but r"\" and r'\' both gave me error. Following one works for me:

workspacePath = r'C:\a.gdb'
datasetName = r'dataset'
featureClassName = r'ofc'
featureClassPath = workspacePath+"\\"+datasetName+"\\"+featureClassName
print featureClassPath

output: C:\a.gdb\dataset\ofc