Python学习第六篇——字典中的键和值

 favorite_language ={
     "jen":"python",
     "sarah":"c",
     "edward":"ruby",
     "phil":"python",
     }
 for name in sorted(favorite_language.keys()):# sort by zimushunxu
     print(name.title()+",thank you for taking the poll.")
 print("\n")
 for name in favorite_language.keys():
     print(name.title()+",thank you for taking the poll.")
 print("\n")
 print("The folllowing languages have been mentioned:")
 for language in favorite_language.values():
     print(language.title())

 print("\nthe following languages have been mentioned:")
 for language in set(favorite_language.values()):
     print(language.title())

本程序的目的在于访问字典中的键和值.

1 访问键可以用.keys()的方式，实际上，默认的就是访问键，比如 name in favorite_language和 name in favorite_language.keys()中的name 都表示了键

2 访问值可以用.values()类

3 sorted()可以对特定的变量以特定的方式排序,比如如果是数字，以大小的顺序排序，如果是字符串,以首字母出现的顺序排序