Python檔案writelines()方法

2019-10-16 23:05:36

Python檔案的writelines()方法將一串字串寫入到檔案。該序列可以是生成字串的任何可疊代物件,通常是字串列表。此方法沒有返回值。

語法

以下是writelines()方法的語法 -

fileObject.writelines( sequence )

引數

  • sequence - 這是要寫入檔案的字串序列。

返回值

  • 此方法不返回任何值。

範例

假設’foo.txt‘檔案中包含以下行 -

Line No 0 - This is 1st line
Line No 1 - This is 2nd line
Line No 2 - This is 3rd line
Line No 3 - This is 4th line
Line No 4 - This is 5th line
Line No 5 - This is 6th line

以下範例顯示了writelines()方法的用法。

#!/usr/bin/python3
#coding=utf-8


# Open a file in read/write mode
fo = open("foo.txt", "r+")
print ("Name of the file: ", fo.name)

seq = ["This is 6th line\n", "This is 7th line"]
# Write sequence of lines at the end of the file.
fo.seek(0, 2)
line = fo.writelines( seq )

# Now read complete file from beginning.
fo.seek(0,0)
for index in range(7):
  line = next(fo)
  print ("Line No %d - %s" % (index, line))

# Close opened file
fo.close()

執行上面程式碼後,將得到以下結果 -

Name of the file:  foo.txt

Line No 0 - This is 1st line
Line No 1 - This is 2nd line
Line No 2 - This is 3rd line
Line No 3 - This is 4th line
Line No 4 - This is 5th line
Line No 5 - This is 6th line
Line No 6 - This is 7th line

注意: 先建立好 foo.txt 檔案