‘_io.TextIOWrapper’；对象不是python3中的可下标错误

我正在做一个小计划，为我消磨我的一天！我正在读取一个文件，并将每一行存储在一个变量中，如下所示：

cline = f[num_lines]

我不知道为什么这一行会出现错误这是我的完整代码：

import os
number_lines = 1
print('Enter the filepath to the file you want to read.')
fpath = input('Enter: ')
print('okay')
with open(fpath, 'r') as f:
    for line in f:
        cline = f[num_lines]
        originalline = number_lines
        number_lines += 1
        length = len(line)
        if cline[0] == 'e' and cline[1] == 'c' and cline[2] == 'h' and cline[3] == 'o' and cline[4] == '':
          echoing = cline[5:length]
          print(echoing)
        else:
          print('N# Does not recognize that command! In line: ' + str(originalline))

提前谢谢你，我不知道为什么这不起作用。

电话线

cline = f[num_lines] 

不工作，因为

f

是

TextIOWrapper

（或文件）对象，并且它不提供

\uuu getitem\uuuuu

方法，该方法允许

[index]

操作。此外，

num_行

未定义。当前行的内容已经保存在变量

line

中，因此不需要定义

cline

这个版本的代码有效（我将最后的字符串测试修改为

line[4]==”

，因为

line[4]==”

永远不可能为真）

如果您愿意，您可以通过使用内置函数来跟踪第th行编号并测试每行的开头来减少代码量

print("Enter the filepath to the file you want to read.")
fpath = input("Enter: ")
print("okay")
with open(fpath, "r") as f:
    for number_lines, line in enumerate(f, start=1):
        length = len(line)
        if line.startswith("echo "):
            echoing = line[5:length]
            print(echoing)
        else:
            print("N# Does not recognize that command! In line: " + str(number_lines))

print("Enter the filepath to the file you want to read.")
fpath = input("Enter: ")
print("okay")
with open(fpath, "r") as f:
    for number_lines, line in enumerate(f, start=1):
        length = len(line)
        if line.startswith("echo "):
            echoing = line[5:length]
            print(echoing)
        else:
            print("N# Does not recognize that command! In line: " + str(number_lines))