使Python在程序运行时重新读取文件

Question

I am having trouble writing code for this program:

#opening a file

addressbook = open("h:/A453/Address Book/AddressBook1.txt","r+")

line = addressbook.readline()

searchdata = input("Please enter the surname you are looking for ")

if searchdata in line:
    print(line)

All of the above work but it only reads the bottom line of text in the file when I run it. I have researched this on the web but have not found anything useful or understandable. Any help would be appreciated. Thanks.

Answer 1

The problem is that, you are using .readline() which reads only one line from the file to read the whole file you have 2 options: .read() or .readlines()

.read() method It reads the contents of the file in one go and returns a string with all the escape characters and spaces preserved.

.readlines() It reads the file and returns a list of contents of the file whose elements are split() at each newline.

#opening a file

addressbook = open("h:/A453/Address Book/AddressBook1.txt","r+")

line = addressbook.read()

searchdata = input("Please enter the surname you are looking for ")

if searchdata in line:
    print(line)