python学习笔记（6）——fileIO

　　1、open&argument

 1 my_file = open("output.txt", "w")

　　hint:You can open files in write-only mode ("w"), read-only mode ("r"), readand write mode ("r+"), and append mode ("a", which adds any new data you write to the file to the end of the file).　　

　　2、write

 1 my_list = [i**2 for i in range(1,11)]
 2 print my_list
 3 my_file = open("output.txt", "w")
 4
 5 # Add your code below!
 6 for i in range(len(my_list)):
 7     my_file.write(str(my_list[i]))
 8     my_file.write(‘\n‘)
 9     if i == len(my_list):
10         my_file.close()

　　3、read

1 my_file = open(‘output.txt‘,‘r‘)
2 print my_file.read()
3 my_file.close()

　　4、readline（）

1 my_file = open(‘text.txt‘,‘r‘)
2 for i in range(3):
3     print my_file.readline()
4 my_file.close()

　　5、 with

1 with open("text.txt", "w") as textfile:
2     textfile.write("Success!")