info = data[:min(len(data), 75)

这是另一种解决方案。在测试结束时，你会得到一些关于测试的反馈。

data = {True: data[:75] + '..', False: data}[len(data) > 75]

简单而简短的helper函数:

def truncate_string(value, max_length=255, suffix='...'):
    string_value = str(value)
    string_truncated = string_value[:min(len(string_value), (max_length - len(suffix)))]
    suffix = (suffix if len(string_value) > max_length else '')
    return string_truncated+suffix

使用例子:

# Example 1 (default):

long_string = ""
for number in range(1, 1000): 
    long_string += str(number) + ','    

result = truncate_string(long_string)
print(result)


# Example 2 (custom length):

short_string = 'Hello world'
result = truncate_string(short_string, 8)
print(result) # > Hello... 


# Example 3 (not truncated):

short_string = 'Hello world'
result = truncate_string(short_string)
print(result) # > Hello world

info = (data[:75] + '..') if len(data) > 75 else data

如果您使用的是Python 3.4+，则可以使用textwrap。从标准库中缩短:

Collapse and truncate the given text to fit in the given width. First the whitespace in text is collapsed (all whitespace is replaced by single spaces). If the result fits in the width, it is returned. Otherwise, enough words are dropped from the end so that the remaining words plus the placeholder fit within width: >>> textwrap.shorten("Hello world!", width=12) 'Hello world!' >>> textwrap.shorten("Hello world!", width=11) 'Hello [...]' >>> textwrap.shorten("Hello world", width=10, placeholder="...") 'Hello...'

对于Django解决方案(问题中没有提到):

from django.utils.text import Truncator
value = Truncator(value).chars(75)

看看Truncator的源代码来理解这个问题: https://github.com/django/django/blob/master/django/utils/text.py#L66

关于Django的截断: Django HTML截断