Question

我尝试使以下代码正常工作：

try:
    x = int(input())
except ValueError as var:
    #print the input of the user

如果我尝试print(var)，它将打印错误行而不是用户的原始输入例如，如果用户要插入bla而不是整数，我想打印bla

P.S我不能改变行x = int(input())，否则我会轻易解决它

Answer 1

打印var时会出现什么？在您提供该信息之前，这是一个可能的hackish解决方案：

try:
    x = int(input())
except NameError as var:
    e = str(var)
    print e[6:-16]

假设var等于

NameError: name 'user_input' is not defined

其中user_input是用户的输入。

编辑：这篇文章假设代码在Python 2.x中运行，而它似乎在运行Python 3。如果人们想知道Python 2的话就把它留下来

Answer 2

我会改变x = int(input())行，但既然你问，这是一个丑陋的黑客利用ValueError消息的格式：

invalid literal for int() with base 10: 'foobar'

首先将其拆分为:并删除周围的'：

try:
    x = int(input())
except ValueError as e:
    original_input = str(e).split(":")[1].strip()[1:-1]
    print(original_input)

顺便说一下，如果您仍在使用Python 2.x，则应使用raw_input代替input 。事实上，如果可能，旧的input会自动尝试转换为int：

try:
    x = int(raw_input())
except ValueError as e:
    original_input = str(e).split(":")[1].strip()[1:-1]
    print original_input

Answer 3

这是从传递的错误消息中读取输入的hack。它正确处理输入字符串和反斜杠中的引号。

#We get input from the user
try:
    x = int(input())
except ValueError as var:
    #we need to find the text between the quotes in the error message
    #but we don't know what kind of quote it will be. We will look for
    #the first quote which will be the kind of quotes.

    #get the location or existence of each kind of quote
    first_dquote = str(var).find('"')
    first_squote = str(var).find("'")

    used_quote = 0
    #if double quotes don't exist then it must be a single quote
    if -1 == first_dquote:
        used_quote = first_squote
    #if single quotes don't exist then it must be a dubble quote
    elif -1 == first_squote:
        used_quote = first_dquote
    #if they both exist then the first one is the outside quote
    else: used_quote = min(first_squote,first_dquote)

    #the output is what is between the quotes. We leave of the end
    #because there is the end quote.
    output = str(var)[used_quote+1:-1]

    #but the error message is escaped so we need to unescape it
    output = bytes(output,"utf_8").decode("unicode_escape")

    #print the output
    print(output)

Python从int（input（））异常中检索字符串输入

3 个答案: