用未知的内部替换多个不同的字符串？

Question

我正在尝试替换文本文件中以以下内容开头的所有多行：setAttr ".os" 并以：setAttr ".sf".

结尾

由于开始和结束之间的界线未知且可变...

问题是如果变量 old 找到不同的结果，它只会替换一次。

firstFrame = str(80)
lastFrame = str(200)

begin = 'setAttr ".os" '
ending = 'setAttr ".sf" '

new = """setAttr ".os" """+ firstFrame +""";
setAttr ".oe" """+ lastFrame +""";
setAttr ".ss" """+ firstFrame +""";
setAttr ".se" """+ lastFrame +""";
"""

with open('pathToFile.txt', 'r') as read_stream:
    file1 = read_stream.read()
    f1_start = file1.index(begin)
    f1_end = file1.index(ending, f1_start)
    old = file1[f1_start:(f1_end+18)]
    file1 = file1.replace(old, new )
    with open('pathToFile.txt', 'w') as read_stream:
        read_stream.write(file1)

我认为我的错误在行：

old = file1[f1_start:(f1_end+18)]

但是我不知道如何使这一行变量，

Answer 1

您不能在阅读原始文件时向其写入行。我在这里使用一个单独的名称。最后你必须rename/remove。

我会一行一行地做。

firstFrame = '80'
lastFrame = '200'

begin = 'setAttr ".os" '
ending = 'setAttr ".sf" '

new = f"""\
setAttr ".os" {firstFrame};
setAttr ".oe" {lastFrame};
setAttr ".ss" {firstFrame};
setAttr ".se" {lastFrame};"""

fout = open('pathToNewFile.txt','w')
looking = begin
skipping = False
for line in open('pathToFile.txt'):
    if line.startswith(begin):
        skipping = True
        fout.write(new)
    elif line.startswith(ending):
        skipping = False
    elif not skipping:
        fout.write(line)

用未知的内部替换多个不同的字符串？

Replace multiple different strings with unknown inside?

python

replace

python-2.7