1.writelines() Direct write
l=["A","B","C","D"] f=open("k.txt","w") f.writelines(l) f.close()
This method writes directly to the list element

2.str Write to string
l=["A","B","C","D",1,2,3] f=open("k.txt","w") f.write(str(l)) f.close()
This method converts the entire list to a string and writes it to the ,

3.for Cyclic write
l=["A","B","C","D"] f=open("k.txt","w") for line in l: f.write(line+'\n')
The advantages of this method are , Each element is a word , Each element can be modified at write time , And can wrap . But pay attention
There is no way to add the number in the list to the character you want to add (int Type cannot be associated with str Add )

4. use .join Function modification list
l=["A","B","C","D"] str = '\n' f=open("k.txt","w") f.write(str.join(l))
use join Can be very good to add you want to add characters and numbers , Very flexible , Recommended , If there is a numeric type in the list , You can use it first str Write after conversion

Read data


If used read To read , Is returned as a string type , And the list can only be of string type (str), A numeric type cannot exist , If there is a number, an error will be reported

readline And read identical   ,

If used readlines To read , The default return is list type , And one element of the list is one line element

At this time, the data can be well processed

Read the number in the list , Provide a simple method
for line in l: if "0" in next or "1" in next: