Question

我有一个.ics文件，我需要从

中删除VTIMEZONE行

从BEGIN：VTIMEZONE到END：VTIMEZONE

删除所有内容的最简单方法是什么？

BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//TEST//TEST//EN
BEGIN:VTIMEZONE
TZID:UTC+11
BEGIN:STANDARD
DTSTART;VALUE=DATE:20170101
TZNAME:UTC+11
TZOFFSETFROM:+1100
TZOFFSETTO:+1100
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DESCRIPTION:Testing
DTEND;TZID=UTC+11:20170228T233000
DTSTAMP:20170227T064302Z
DTSTART;TZID=UTC+11:20170228T230000
UID:1961094_636238800000000000
END:VEVENT
END:VCALENDAR

我这样做的原因是iCalendar库在包含vtimezone时没有解析文件。 DTSTART和DTEND不能是进程。

Answer 1

我没有日历文件的经验，但是以下代码（提供注释以供解释）：

with open("help.ics","r") as input_file:
    #read in each line as a list
        input_lines = input_file.readlines()

        with open("newhelp.ics","w") as output_file:      

            #variable to determine whether to write file to new file or not
            keep_lines = True

            #loop thorugh every line
            for line in input_lines:
                if line == "BEGIN:VTIMEZONE\n":
                    #When the BEGIN:VTIMEZONE line is reached, stop writing lines
                    keep_lines = False

                if keep_lines:
                    #write line to new file if the line is not inbetween the VTIMEZONE lines
                    output_file.write(line)

                elif line == "END:VTIMEZONE\n":
                    #When the END:VTIMEZONE line is reached, start writing lines again
                    keep_lines = True

将输出一个新文件：

BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//TEST//TEST//EN
BEGIN:VEVENT
DESCRIPTION:Testing
DTEND;TZID=UTC+11:20170228T233000
DTSTAMP:20170227T064302Z
DTSTART;TZID=UTC+11:20170228T230000
UID:1961094_636238800000000000
END:VEVENT
END:VCALENDAR

来自输入：

BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//TEST//TEST//EN
BEGIN:VTIMEZONE
TZID:UTC+11
BEGIN:STANDARD
DTSTART;VALUE=DATE:20170101
TZNAME:UTC+11
TZOFFSETFROM:+1100
TZOFFSETTO:+1100
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DESCRIPTION:Testing
DTEND;TZID=UTC+11:20170228T233000
DTSTAMP:20170227T064302Z
DTSTART;TZID=UTC+11:20170228T230000
UID:1961094_636238800000000000
END:VEVENT
END:VCALENDAR

替代地

要保存要保留的行，您可以使用相同的方法，而不是打开新文件并在那里写行，您可以创建新列表lines_to_keep =[]并执行lines_to_keep.append(line)而不是output_file.write(line)：

lines_to_keep = []

with open("help.ics","r") as input_file:
        input_lines = input_file.readlines()

        keep_lines = True

        for line in input_lines:

            if line == "BEGIN:VTIMEZONE\n":
                keep_lines = False

            if keep_lines:

                #add the line to the list instead of writing it to a new file
                lines_to_keep.append(line)

            elif line == "END:VTIMEZONE\n":
                keep_lines = True

然后lines_to_keep列表包含您希望保持运行的所有行：

for line in lines_to_keep:
    print(line)

输出：

BEGIN:VCALENDAR

VERSION:2.0

PRODID:-//TEST//TEST//EN

END:VTIMEZONE

BEGIN:VEVENT

DESCRIPTION:Testing

DTEND;TZID=UTC+11:20170228T233000

DTSTAMP:20170227T064302Z

DTSTART;TZID=UTC+11:20170228T230000

UID:1961094_636238800000000000

END:VEVENT

END:VCALENDAR

请注意，列表中的实际项目如下所示：

['BEGIN:VCALENDAR\n', 'VERSION:2.0\n', 'PRODID:-//TEST//TEST//EN\n', 'END:VTIMEZONE\n', 'BEGIN:VEVENT\n', 'DESCRIPTION:Testing\n', 'DTEND;TZID=UTC+11:20170228T233000\n', 'DTSTAMP:20170227T064302Z\n', 'DTSTART;TZID=UTC+11:20170228T230000\n', 'UID:1961094_636238800000000000\n', 'END:VEVENT\n', 'END:VCALENDAR']

\n代表一个新行。没有它，如果你要将这些行写入新文件，它们将被写在同一行。 \n首先出现在那里，因为它由input_file.readlines()读入。

如果您想将这些转换为实际行的字符串，例如'BEGIN:VCALENDAR'而不是'BEGIN:VCALENDAR\n'，则可以遍历列表中的每一行，如果它以'结尾'结尾\ n'删除它：

for line_index in range(len(lines_to_keep)):
    if lines_to_keep[line_index].endswith('\n'):
        lines_to_keep[line_index] = lines_to_keep[line_index][:-1]

如果以'\ n'结尾，那么每行都会更改每行，而不是最后两个字符。

Answer 2

感谢Adam的帮助，这是我的最终代码。我的微妙区别是我写入IO内存（import io）而不是文件。

ics_temp=io.StringIO()
with open(ics_local,"r") as input_file:
    #read in each line as a list
    input_lines = input_file.readlines()
    ics_temp=io.StringIO()
    keep_lines = True   #variable to IOStream or not
    for line in input_lines:    #loop thorugh every line
        if line == "BEGIN:VTIMEZONE\n":
            #When the BEGIN:VTIMEZONE line is reached, stop writing lines
            keep_lines = False
        elif line == "END:VTIMEZONE\n":
            #When the END:VTIMEZONE line is reached, start writing lines again
            keep_lines = True
        if keep_lines==True and line != "END:VTIMEZONE\n":
            ics_temp.write(line)       #write line to ioString inbetween the VTIMEZONE lines

ics_file=ics_temp.getvalue()
ics_temp.close()
print(ics_file)

删除python 3.0中的某些行

2 个答案:

替代地