变量没有定义，但是

Question

I have seen this question multiple times but none of them can apply to my code and none of it makes sense to my code. So I am sorry for asking this question.

I have written up a code where the data from previous inputs are written into a csv file. The name of the variable is called file and i have numerous of these for different inputs. But when I try to close the csv it comes up with the error: NameError: name 'file' is not defined

Here is the code:

if classCode=="1":
  file=open("class1.csv","w")
  file.write("name, correct\n" + name + "," + str(correct) + "\n")

elif classCode=="2":
  file=open("class2.csv","w")
  file.write("name, correct\n" + name + "," + str(correct) + "\n")

elif classCode=="3":
  file=open("class3.csv","w")
  file.write("name, correct\n" + name + "," + str(correct) + "\n")

file.close()

I don't know why it says that 'file' isn't defined when I clearly have for all three. Am i just being stupid?

Answer 1

What happens if the class code is not 1,2 or 3. If all class code do the same thing you can make the filename dynamic, instead of repeating the code several times.

class_file=open("class{}.csv".format(classCode),"w")
class_file.write("name, correct\n" + name + "," + str(correct) + "\n")
class_file.close()

Answer 2

file variable will only declare when classCode is either "1", "2" or "3" otherwise it will not declare and error will come.

you should make sure either control goes to any of the if statement or you should declare this variable outside If statement.