Use Arcade to Calculate Field Based on Options from Another Field

ZachBodenner

Hello,

I've got an Arcade question. I have a feature set of points with an attribute "Type" that details the feature type. I have another attribute that is a numeric ID that corresponds to the text attribute Type. Example: Hydrant =1, Curb Stop = 2 etc. What's the best way to write an attribute rule in Arcade that will populate the numeric ID based on the value from the text type? My knee jerk is to do a super long If/Else exchange to the effect of:

var waterType = $feature.Type
if (waterType='Hydrant'){
return 1;
}
if(waterType='Curb Stop'){
return 2;
}
etc

However, there are like, 60 possible types which strikes me as a bit onerous to put into an if statement like that. Is there a better way?

kenbuja

Here are two possible ways of doing it. It is a little onerous to build it for your 60 types either way, but a little easier than using if statements.

Using a Dictionary

var dict = {
  'Hydrant': 1,
  'Curb Stop': 2
};
var waterType = $feature.Type
return dict[waterType];

Using a When function

var waterType = $feature.Type;
when (waterType == 'Hydrant', 1,
      waterType == 'Curb Stop', 2,
      -9999 //default value for any other type
      )