"我的Python代码在write()函数中写入随机符号的原因 (Python 2.7)"

Question

我有这个Python代码：

f = open("database.txt", "r+")

f.write("Hello!")
print f.read()
f.close()

当我运行代码时，Idle会显示：-t

但是当我看到database.txt文件时，这是它的内部内容：

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Answer 1

试着这样做：

with open("database.txt", "w") as f:
    f.write("Hello!")

with open("database.txt", "r") as f:
    for line in f:
        print line

您可以避免使用with statement手动关闭文件。 另外，一旦你写了文件，你就可以阅读它。 一般来说，最好将对文件的读写访问分开。除非你真的需要两者兼而有之。你知道吗