当csv文件为n时，它将显示为空

Question

我正在创建一个程序，该程序将把投票信息写入一个新的结果文件，在写入所有可用的投票选项之前，我需要检查文件是否为空。（否则，每次有人投票时，数据都会覆盖已经输入的结果）。我的问题是，当我运行这段代码时，它不会返回任何东西。在这里：

def VOTE1():
        Data = ("VOTE")
        voteChoice = OptionAmount.get()
        with open('EXISTINGVOTE.CSV') as infile:
            reader = csv.DictReader(infile)
            for row in reader:
                if voteChoice == row['TITLE NAME']:
                    f = open('{}.csv'.format(row['TITLE NAME']), "w")
                    f.close()
                    with open('{}.csv'.format(row['TITLE NAME']), "r") as f:
                        VoteRead = csv.reader(f, delimiter=",")
                        for row in VoteRead:
                            for field in row:
                                if field == Data:
                                    print("Empty file")
                                else:
                                    print("There is data in here")
                else:
                    print("Not this one")

我应该得到一个声明说“空文件”或者“这里有数据”

Answer 1

当前您通过打开文件进行写入来销毁文件内容

f = open('{}.csv'.format(row['TITLE NAME']), "w")

…然后你读了现在空的新文件。你知道吗

open('{}.csv'.format(row['TITLE NAME']), "r") as f

您可能要做的是打开文件以附加数据：

if voteChoice == row['TITLE NAME']:
    # two lines deleted
    with open('{}.csv'.format(row['TITLE NAME']), "a") as f: