为什么Python的CSV模块在我尝试运行程序后打开CSV文件时会变为只读模式？

Question

我使用一个程序（如下）来查看两个CSV文件之间某些列的相似性，然后在数据与特定规范匹配时创建第三列（两列相同，但第三列不同），这样我就可以更新电子邮件列表。在

当我试图打开结果.csv文件运行程序后，Windows Excel将只以只读模式打开程序。在

有什么想法吗？在

我的代码是：

import csv

sample_data = open("sample.csv", "r")
lib_data = open("library.csv", "r")
csv1 = csv.reader(sample_data)
csv2 = csv.reader(lib_data)

results = open("results.csv", "w")
res_csv = csv.writer(results)

limit = 1071
limit2 = 1001

x = 0
y = 0

while (y != limit):
    row1 = csv1.__next__()
    while (x != limit2):
        row2 = csv2.__next__()
        if (row1[0] == row2[3] and row1[1] == row2[2] and row1[2] != row2[5]):
            print ("SAMPLE:")
            print (row1[0], ", ", row1[1], ", ", row1[2])
            print ("LIBRARY:")
            print (row2[3], ", ", row2[2], ", ", row2[5])
            print("\n")
            res_csv.writerow(row1)
        x = x+1
    y = y+1
    x = 0
    lib_data.seek(0)

Answer 1

使用with确保文件将正确关闭：

with open("sample.csv", "r") as sample_data:
    with open("library.csv", "r") as lib_data:
        with open("results.csv", "w") as results:
            # other code

如果使用Python>；=2.7，甚至可以将多个变量放入一个with。在