programming-for-dummies

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Storing Data in Text Files
Creating a text file typically requires three steps:
1. Name a text file.
2. Assign a variable to that text file.
3. Store one or more lines of text in the text file.
The following Python language example creates a text file named
“mytext.txt” and stores the names Joe Smith, Mary Evans, and
Donna Dickens in that file:
names = “””Joe Smith
Mary Evans
Donna Dickens”””
myfile = open(“mytext.txt”, “w”)
myfile.write(names)
myfile.close()
The Python program follows these steps:
1. This Python program stores the names Joe Smith, Mary Evans, and
Donna Dickens in a names variable.
2. This program creates (opens) a text file named “mytext.txt” and
assigns this filename to a “myfile” variable.
The “w” symbol tells the program to open the “mytext.txt” file so
that you can write or add data to that text file.
The “w” symbol tells the computer to erase everything inside the
“mytext.txt” text file. If you want to add new data to a text file without
erasing its entire contents, replace the “w” symbol with the “a”
(append) symbol instead, like this:
scraps = open(“mytext.txt”, “a”)
scraps.write(“\nSal Lankins”)
scraps.close()
The preceding three lines of code would open the “mytext.txt”
file, add a new line (the “\n” characters), and tack the name “Sal
Lankins” at the end of the text file.
3. The “myfile.write(names)” command tells the computer to take
the data stored in the names variable and store (write) it in the text
file assigned to the “myfile” variable.
4. The “myfile.close()” command tells the computer to shut or close
the file.