Python檔readlines()方法

Python檔的readlines()方法使用readline()讀取並返回一個包含行的列表直到EOF。 如果可選的sizehint參數存在，則不讀取到EOF，它讀取總共大約為sizehint大小的字串(可能在舍入到內部緩衝區大小之後)的整行。

僅在遇到EOF時才返回空字元串。

語法

以下是readlines()方法的語法 -

fileObject.readlines( sizehint );

參數

• sizehint − 這是要從檔讀取的位元組數。

返回值

• 此方法返回包含行的列表。

示例

假設’foo.txt‘檔中包含以下行 -

This is 1st line
This is 2nd line
This is 3rd line
This is 4th line
This is 5th line

以下示例顯示了readlines()方法的用法。

#!/usr/bin/python3

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

line = fo.readlines()
print ("Read Line: %s" % (line))

line = fo.readlines(2)
print ("Read Line: %s" % (line))

# Close opened file
fo.close()

執行上面代碼後，將得到以下結果 -

Name of the file:  foo.txt
Read Line: ['This is 1st line\n', 'This is 2nd line\n',
   'This is 3rd line\n', 'This is 4th line\n', 'This is 5th line\n']
Read Line: