IO.UnsupportedOperation:不可写

Question

我制作了一个程序，它在.txt文件中存储一个带有名称的分数。然而，我想然后打印字母顺序的名称附加到分数。但是，当我运行这个程序时，它会产生错误io.UnsupportedOperation: not writable，这里是我的代码：

            file = open(class_name , 'r')       #opens the file in 'append' mode so you don't delete all the information
            name = (name)
            file.write(str(name + " : " )) #writes the information to the file
            file.write(str(score))
            file.write('\n')
            lineList = file.readlines()
            for line in sorted(lineList):
                print(line.rstrip());
                file.close()

Answer 1

您已打开文件只读，然后尝试写入它。当文件未打开时，您将尝试从其中读取，即使处于追加模式，文件指针也将位于文件的末尾。试一试：

class_name = "class.txt"
name = "joe"
score = 1.5
file = open(class_name , 'a')       #opens the file in 'append' mode so you don't delete all the information
name = (name)
file.write(str(name + " : " )) #writes the information to the file
file.write(str(score))
file.write('\n')
file.close()
file = open(class_name , 'r') 
lineList = file.readlines()
for line in sorted(lineList):
    print(line.rstrip());
file.close()

Answer 2

您正在尝试多次关闭该文件。试试这个：

with open(class_name , 'w+') as file:
    name = (name)
    file.write(str(name + " : " )) #writes the information to the file
    file.write(str(score))
    file.write('\n')
    for line in sorted(lineList):
        print(line.rstrip()); 

Answer 3

您正在以读模式r打开文件，这只允许读取文件，r+允许读取和写入文件。您可以参考python文档