drop list from field to execute SQL request

Question

I'm trying to create a python script that allows a selection attribute based on the name of a field in the attribute table of a layer.

I would like to configure my script such a way that permits the user to select the SOURCE NAME from a drop-down list. Here's the code I have written:

import arcpy
arcpy.env.workspace = 'in_memory'
arcpy.env.overwriteOutput = True 
mxd = arcpy.mapping.MapDocument("CURRENT")
df = arcpy.mapping.ListDataFrames(mxd)[0]
PosteLayer=arcpy.GetParameterAsText(0)
field="NAME_SOURCE"
rows=arcpy.da.SearchCursor(PosteLayer,["NAME_SOURCE"])
list=[]
for row in rows:
 if str(row[O]) not in list:
 liste.append(row[0])
POSTES=liste
POSTES=arcpy.GetParameterAsText(1)

I'm using the Advanced Version Of Arcgis 10.2

• PolyGeo: You need to look into tool validation on a Python Script tool.
• Lahlou Imane: @PolyGeo what can i add in my case i never work with the tool validation before
• PolyGeo: Whenever I need to do it I go to the Help to re-learn how.
• Lahlou Imane: that's what i have done already before posting this i really need help
• dslamb: Here is an example that uses the Python Toolbox. I find it a little easier to use validation in that context than the tbx. gis.stackexchange.com/questions/82473/…

Answer 1

First: you should make a toolbox with a script set the parameters the name "List of Source Name" the data type "string" the filter "value list as in picture: enter image description here

Second: select Validation the edit button write under the (def updateParameters(self)) the following:

def updateParameters(self):
 #define the path of your feature class
 fc="D:/000/test.shp"
 #define the the name of the field
 col= ("SOURCENAME")
 self.params[0].filter.list = [str(val) for val in 
 sorted( 
 set( 
 row.getValue(col) 
 for row in arcpy.SearchCursor(fc, None, None,col)))] 
 if self.params[0].value not in self.params[0].filter.list: 
 self.params[0].value = self.params[0].filter.list[0]
 return

Third: create a tool script and write the following:

import arcpy
mxd = arcpy.mapping.MapDocument("CURRENT")
currentlayer = arcpy.mapping.ListLayers(mxd, "*") [0]
inputLayer = arcpy.MakeFeatureLayer_management(currentlayer) 
TWN = arcpy.GetParameterAsText(0)
query = "SOURCENAME = '" + TWN + "'"
arcpy.SelectLayerByAttribute_management(currentlayer, "NEW_SELECTION", query )
count = arcpy.GetCount_management(currentlayer)
arcpy.AddMessage("thes selected are: "+str(count))

or you can write in the validation script the following:

def updateParameters(self):
 #define the top layer in the mapview
 mxd = arcpy.mapping.MapDocument("CURRENT")
 fc = arcpy.mapping.ListLayers(mxd, "*") [0]
 #define the the name of the field
 col= ("SOURCENAME")
 self.params[0].filter.list = [str(val) for val in 
 sorted( 
 set( 
 row.getValue(col) 
 for row in arcpy.SearchCursor(fc, None, None,col)))] 
 if self.params[0].value not in self.params[0].filter.list: 
 self.params[0].value = self.params[0].filter.list[0]
 return