Replace multiple different strings with unknown inside?-CodePudding

I'm trying to replace alls multiples lines in a text file who are beginning by: setAttr ".os" and ending by: setAttr ".sf".

As lines between begin and ending are unknown and variable...

The issue is that it only replace one occurrence, if variable old find differents results.

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)

I think my error is at line:

old = file1[f1_start:(f1_end 18)]

But I doesn't know how to make this line variable,

CodePudding user response：

You can't write lines to your original file while you are reading it. I am using a separate name here. You'll have to rename/remove at the end.

I would just do it line by line.

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)