Python “以 10 为基数的 int() 的无效文字：”这实际上是什么意思？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/30903967/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
"invalid literal for int() with base 10:" What does this actually mean?
提问by Andrew
Beginner here! I am writing a simple code to count how many times an item shows up in a list (ex. count([1, 3, 1, 4, 1, 5], 1)would return 3).
初学者在这里！我正在编写一个简单的代码来计算一个项目在列表中出现的次数（例如count([1, 3, 1, 4, 1, 5], 1)将返回 3）。
This is what I originally had:
这是我最初拥有的：
def count(sequence, item):
s = 0
for i in sequence:
if int(i) == int(item):
s += 1
return s
Every time I submitted this code, I got
每次我提交这个代码，我得到
"invalid literal for int() with base 10:"
“以 10 为基数的 int() 的无效文字：”
I've since figured out that the correct code is:
我后来发现正确的代码是：
def count(sequence, item):
s = 0
for i in sequence:
if **i == item**:
s += 1
return s
However, I'm just curious as to what that error statement means. Why can't I just leave in int()?
但是，我只是好奇那个错误声明是什么意思。为什么我不能直接离开int()？
回答by recursive
The error is "invalid literal for int() with base 10:". This just means that the argument that you passed to intdoesn't look like a number. In other words it's either empty, or has a character in it other than a digit.
错误是“以 10 为基数的 int() 的无效文字：”。这只是意味着您传递给的参数int看起来不像数字。换句话说，它要么是空的，要么是数字以外的字符。
This can be reproduced in a python shell.
这可以在 python shell 中重现。
>>> int("x")
ValueError: invalid literal for int() with base 10: 'x'
回答by udarH3
You could try something like this if letters for example, occur in your sequence:
例如，如果字母出现在您的序列中，您可以尝试这样的操作：
from __future__ import print_function
def count_(sequence, item):
s = 0
for i in sequence:
try:
if int(i) == int(item):
s = s + 1
except ValueError:
print ('Found: ',i, ', i can\'t count that, only numbers', sep='')
return s
print (count_([1,2,3,'S',4, 4, 1, 1, 'A'], 1))
