列表的title（）如何使用

humanoids

favorite_languages={
    'jen':['C','R'],
    'sarah':['perl'],
    'ben':['python','go'],
    'phil':['shell'],
    }
for name,languages in favorite_languages.items():
   
    if (len(languages))>1:
        print('\n'+name.title()+"'s favorite language are ; ")
        for lg in languages:
            print('\t' + lg.title())
    else:
        print('\n'+name.title()+"'s favorite language is ; ")
   
        print('\t'+ str(languages[0]))

得到的结果是
Jen's favorite language are ;
        C
        R

Ben's favorite language are ;
        Python
        Go

Sarah's favorite language is ;
        perl

Phil's favorite language is ;
        shell


当代码改为：
favorite_languages={
    'jen':['C','R'],
    'sarah':['perl'],
    'ben':['python','go'],
    'phil':['shell'],
    }
for name,languages in favorite_languages.items():
   
    if (len(languages))>1:
        print('\n'+name.title()+"'s favorite language are ; ")
        for lg in languages:
            print('\t' + lg.title())
    else:
        print('\n'+name.title()+"'s favorite language is ; ")
   
        print('\t'+ language.title())      #修改的部分

问题在于：
第一个if后面    print('\t' + lg.title())   可以正常输出结果
  而 else：  后面print('\t'+ language.title())      
就报错说      print('\t'+ languages.title())
AttributeError: 'list' object has no attribute 'title'

冬雪雪冬

lg是字符串有title方法。
languages是列表没有title方法。

jackz007

1. favorite_languages = {
   
2.     'jen':['C','R'],
   
3.     'sarah':['perl'],
   
4.     'ben':['python','go'],
   
5.     'phil':['shell'],
   
6. }
   
7. 
   
8. for name , languages in favorite_languages . items():
   
9.     if (len(languages)) > 1:
   
10.         print('\n' + name . title() + "'s favorite language are ; ")
    
11.         for lg in languages:
    
12.             print('\t' + lg.title())
    
13.     else:
    
14.         print('\n' + name . title() + "'s favorite language is ; ")
    
15.         print('\t'+ languages[0] . title())  # 【修改】: languages 是只有一个元素的列表，仍然需要通过切片操作才能索引到字符串

复制代码

        print('\t'+ languages[0] . title())

zltzlt

列表没有 title 方法，而字符串有 title 方法。

humanoids

jackz007 发表于 2019-9-21 23:04
print('\t'+ languages[0] . title())

好的，谢谢，理解了