python - Convert string in Class name (from appengine datastore to class) -

-

संभव डुप्लिकेट:

मैं एक अनुप्रयोग विकसित करने के लिए एपेंजिन का उपयोग कर रहा हूं। आदर्श रूप से मैं एक नए प्रकार (जिसे पकाने की विधि कहा जाता है) को परिभाषित करना चाहूंगा: 

  वर्ग पकाने की विधि (डीबी। मॉडल): सामग्री = डीबी। लिस्टप्रॉपर्टी (प्रकार) मात्रा = डीबी। लिस्टप्रॉपर्टी (इंट)

हालांकि ऐसा लगता है कि आप "प्रकार" को सूचीप्रॉपर्टी में वर्ग के मूल्य के रूप में नहीं उपयोग कर सकते हैं मैं ListProperty का उपयोग करने के बजाय, ListStringProperty का उपयोग करने और तार के नामों को तार के रूप में सहेजने की बजाय सोच रहा था। हालांकि, मैं एक स्ट्रिंग को क्लास के नाम में कैसे रूपांतरित कर सकता हूं, इसलिए मैं इस तरह से लिख सकता हूँ: class_str class_str ()। )

अग्रिम धन्यवाद, जोस

मैं सुझाव है कि आप घटक को तारों की सूची बनाते हैं, इसे अपने सेवकों की pickle.dnd से भरें और पुनर्प्राप्ति पर, pickle.loads का उपयोग करें

अचार करें प्रकार "नाम से" प्रकार, इसलिए कुछ बाधाएं हैं (अनिवार्य रूप से, प्रकार के शीर्ष स्तर पर रहना चाहिए कुछ मॉड्यूल), लेकिन प्रकार के नामों की अपनी खुद की सीरियललाइजेशन (और, विशेषकर, डी सीरियलिज़टन) करने से यह बहुत आसान है, जो अनिवार्य रूप से आपको काम का एक सा दोहराएगा जो कि pickle < / कोड> पहले से ही आपकी ओर से कर सकता है! -)


Comments

Post a Comment

Popular posts from this blog

Indexing in SQL -

-
My table has 10 columns .... What column do I choose to create an index? Is there a guideline rule to do this? What are the disadvantages of indexes? What if I update the column which is part of the index? Does this reduce performance of INDEXES? from other posts: 1.1 You should make indexes on columns that are often used in the WHERE section. 1.2 You should be indexed on the columns you use repeatedly to come into the columns. 1.3 You should make indexes on columns that are often used 1.4 You get indexed on the columns The table should contain some of the same values ​​or unique values. 1.5 You should not index small tables (tables using only a few blocks) because a full table scan can be faster than the indexed query. 1.6 If more than one column is often used in the WHERE section in a converged index, then first create the most selected columns, pre-create in the index statement. 1.7 column has many nulls and you do not search for zero-value v...
Read more

objective c - iPhone and it's wireless area -

-
Is this a way to find other iPhones in the category of wireless areas? So I give an example. I'm staying at the airport somewhere I have an iPhone too. I and the other iPhone owners are playing the same game. Is there any way to warn me and the other player that we are close to each other? Does this work even if we are not on the same wireless network, or there is no wireless? And if there is any way to do this, can you give me some starting point? Like a link where I can learn something like this or maybe this is probably the name of this process, because I do not know how to search about this topic in Google. Thanks in advance! Can be completed with peer-to-peer discovery and connectivity you are describing Game Kit Framework Originally I thought it works only through Bluetooth, but after watching it immediately, it seems that WiFi is also supported. Hope it helps!
Read more

multithreading - Do lock objects in Java need to be static? -

-
I know in C # when you have an object that you want to use as a lock for multi-threading You must declare it stable inside a class, which class instances will be running in different threads. Is this also true for Java? Some examples online only begin declaring the last object as a lock object ... EDIT: I have a resource that I want to limit to only one thread access at a time. A class that extends the thread will be used to create many instances and will start at the same time. Thanks Depending on which context they are used they will be used. If you want a per-instance lock, go away still . If you want a per-class lock, use still in addition to actually put it the last .
Read more