Question

我的问题是，在python首次读取原始输入后，它随后不再正确读取输入。我已经尝试了很多东西，但我似乎无法得到它。我做错了什么？

file_path = 'C:\\Users\\Neo\\My Documents\\Python Scripts\\FTC Scouting\\sample.txt'
file = open(file_path, 'r')
Team_Numbers = []

tNum = 'Team Number: '
tName = 'Name: '
ui = ''

def list_teams(n):
    count = 0
    if n == '1':
        for line in file:
            check = line.find(tNum)
            if not check == -1:        
                print line[len(tNum):]    #prints everything after the Team Number: 
            count += 1

    elif n == 2:
        for line in file:
            check = line.find(tName)
            if not check == -1:
                print line[len(tName):]    #prints everything after the Team Number: 
            count += 1

while not ui == 'end':

    ui = raw_input('1: to list Team Numbers\n2: to list Names\n')
    list_teams(ui)


file.close()

Answer 1

Python是强类型的。

elif n == '2':

Answer 2

正在阅读输入。只是当你读过一次文件时，你就完成了;下次迭代时，文件不会从一开始就神奇地开始读取。所以你的for line in file:工作一次，然后再不起作用，因为文件结尾后没有任何内容！要解决此问题，只需将file.seek(0)放在list_teams()函数的末尾即可;这会将文件重置为开头。

也可能存在其他问题（Ignacio发现了一个错误并且还有其他优化措施）但这可能是您的直接问题。

Answer 3

您可以重新查看代码，使其更具Pythonic，减少冗余并增加可读性

首先使用list或字典或命名元组轻松克服的重复代码块，只是list

的示例

keys = ['Team Number: ', 'Name: ']
def list_teams(n):
    count = 0
    try:
        for line in file:
            check = line.find(keys[n])
            if not check == -1:        
                print line[len(keys[n]):]    #prints everything after the Team Number: 
            count += 1
except IndexError:
    None #Or Any appropriate Error Checking

现在是第二部分。您只需使用string.partition

，而不是使用查找然后编制索引

keys = ['Team Number: ', 'Name: ']
def list_teams(n):
    count = 0
    try:
        for line in file:
            print line.partition(keys[n])[2]
            count += 1
except IndexError:
    None #Or Any appropriate Error Checking

最后看来，对list_teams的多次调用都会失败，因为你正在重新结束。一种解决方案是

keys = ['Team Number: ', 'Name: ']
def list_teams(n):
    count = 0
    with open(file_path,'r') as f:
        try:
            for line in file:
                print line.partition(keys[n])[2]
                count += 1
    except IndexError:
        None #Or Any appropriate Error Checking

或者，您可以在阅读文件之前始终寻找开头。

keys = ['Team Number: ', 'Name: ']
def list_teams(n):
    file.seek(0)
    count = 0
    try:
        for line in file:
            print line.partition(keys[n])[2]
            count += 1
except IndexError:
    None #Or Any appropriate Error Checking

python输入读错了？

3 个答案: