python - 一次读取4行

Question

我正在尝试一次读取 fastq 文件四行。文件中有几行。但是当我输入代码时，我得到了这个:

Traceback (most recent call last):

File "fastq.py", line 11, in

line1 = fastq_file.readline()

AttributeError: 'str' object has no attribute 'readline'

这是我的代码:

import Tkinter, tkFileDialog #asks user to select a file

root = Tkinter.Tk()
root.withdraw()

fastq_file = tkFileDialog.askopenfilename()

if fastq_file.endswith('.fastq'): #check the file extension
    minq = raw_input("What is your minimum Q value? It must be a numerical value.") #receives the minimum Q value
    while True:
        line1 = fastq_file.readline()
        if not line1:break
        line2 = fastq_file.readline(2)
        line3 = fastq_file.readline(3)
        line4 = fastq_file.readline(4)
    
    txt = open(practice.text)   
    txt.write(line1) #puts the lines into the file
    txt.write("\n")
    txt.write(line2)
    txt.write("\n")
    txt.write(line3)
    txt.write("\n")
    txt.write(line4)
    txt.write("\n")
    print "Your task is complete!"
    
else:
  print "The file format is not compatible with the FastQ reader program. Please check the file and try again."

我该如何解决这个问题，以便我可以将每一行分配给一个字符串，然后将这些字符串写入文本文件中？

Answer 1

您需要先打开文件

while True:
    with open(fastq_file) as fastq_file_open:
        line1 = fastq_file_open.readline()

您可能想在实际进入 while 循环之前打开它们，但我没有其余的代码，所以我无法准确地构造它。