在python中写入文件后，文件处理程序未打印

Question

我正在尝试写入一个文件并在写入后读取。下面是我的代码。

with open('1.txt','w') as fr:
    x = '3'
    fr.write(x)
    with open('1.txt','r') as fr_r:
        fr_w = fr_r.read()
        print (fr_w)

预期输出低于

3

Answer 1

您的代码应阅读（第二个没有缩进）

with open('1.txt','w') as fr:
    x = '3'
    fr.write(x)
with open('1.txt','r') as fr_r:
    fr_w = fr_r.read()
    print (fr_w)

Answer 2

一旦您用'with'语句打开了一个文件。您无需关闭该频道。因此，python开发人员在此块中设置了禁止写入或使用其他权限通道的限制。

                   once read /write permission in opened we cannot add another permission channel in that block or indentation. it should be in seperate indentation like this below as follows``