Question

我写了一个快速脚本，从excel列保存的网站地址列表中删除'http：//'子字符串。功能替换，但不起作用，我不明白为什么。

from openpyxl import load_workbook

def rem(string):
    print string.startswith("http://")    #it yields "True"
    string.replace("http://","")
    print string, type(string)    #checking if it works (it doesn't though, the output is the same as the input)

wb = load_workbook("prova.xlsx")
ws = wb["Sheet"]

for n in xrange(2,698):
    c = "B"+str(n)
    print ws[c].value, type(ws[c].value)   #just to check value and type (unicode)
    rem(str(ws[c].value))    #transformed to string in order to make replace() work

wb.save("prova.xlsx")    #nothing has changed

Answer 1

String.replace(substr)

不会发生，将其更改为：

string = string.replace("http://","")

Answer 2

string.replace(old, new[, max])只返回一个值 - 它不会修改string。例如，

>>> a = "123"
>>> a.replace("1", "4")
'423'
>>> a
'123'

您必须将字符串重新分配给其修改后的值，如下所示：

>>> a = a.replace("1", "4")
>>> a
'423'

所以在你的情况下，你想要改为写

string = string.replace("http://", "")

python：为什么替换不起作用？

2 个答案: