Python access class property from string

Question

I have a class like the following   class User      def   init   self           self data              self other data           def doSomething self  source              if source    other data  how to access self other data   I want to pass a string for the source variable in doSomething and access the class member of the same name   I have tried getattr which only works on functions  from what I can tell  as well as having User extend dict and using self   getitem    but that doesn t work either  What is the best way to do this

User · Answer

getattr x   y   is equivalent to x y setattr x   y   v  is equivalent to x y   v delattr x   y   is equivalent to del x y

User · Answer

x   getattr self  source  will work just perfectly if source names ANY attribute of self  including the other data in your example

User · Answer

A picture s worth a thousand words    gt  gt  gt  class c          pass o   c    gt  gt  gt  setattr o   foo    bar    gt  gt  gt  o foo  bar   gt  gt  gt  getattr o   foo    bar

User · Answer

Extending Alex s answer slightly   class User      def   init   self           self data    1 2 3          self other data    4 5 6      def doSomething self  source           dataSource   getattr self source          return dataSource  A   User   print A doSomething  data   print A doSomething  other data     will yield   1  2  3   4  5  6    However  personally I don t think that s great style - getattr will let you access any attribute of the instance  including things like the doSomething method itself  or even the   dict   of the instance  I would suggest that instead you implement a dictionary of data sources  like so   class User      def   init   self            self data sources                  data    1 2 3                other data   4 5 6                  def doSomething self  source           dataSource   self data sources source          return dataSource  A   User    print A doSomething  data   print A doSomething  other data     again yielding   1  2  3   4  5  6

[python] Python: access class property from string

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