如何更改配置文件 python 行中的值

Question

file = open("my_config", "r")
for line in file:
    change line to "new_line"
   

How I can change a value of parameter in line.

Answer 1

Just to be clear, you open a config file (may we have a example of the structure? If it is a JSON file or similar, it could be easier), loop trough all lines of it and want to change one line?

The best way would be to recreate the file, stocked in a string and then rewrite it.

file = open("my_config", "w")
str_file = ""
for line in file:
    # Change the line here
    str_file += line+'\n'

str_file = str_file.strip() #To remove the last \n

file.write(str_file)
file.close()

EDIT: with your comment QA Answser, I'ld go with:

file = open("my_config", "w")
str_file = ""
for line in file:
    if (line.split(':')[0] == 'SECURITY_LEVEL'):
        line = 'SECURITY_LEVEL:' + VALUE #your new value here
    str_file += line+'\n'

str_file = str_file.strip() #To remove the last \n

file.write(str_file)
file.close()