"Python study notes" Coursera's py4e study notes--file

1. Open File

Use Handle=open (Filename,mode) to open the file. This function will return a handle (which should be translated as "handle") to manipulate the file, and the parameter filename is a string. The parameter mode is optional, ' R ' stands for reading the file, ' W ' represents the Write file.

Cases:

>>> Fhand=open ('mbox.txt','r')
>>> Print (Fhand)
<_io. Textiowrapper name= ' mbox.txt ' mode= ' r ' encoding= ' UTF-8 ' >

The file handle can be thought of as a sequence of strings, and each line of an instance of the document is the contents of the string sequence.

Example: Number of rows of file contents

Fhand=open ('mbox.txt') Count=0 for in Fhand:    count=count+1print('linecount:', count) $ python Open.pyline Count:132045

Example: Retrieving the contents of a file

Fhand = open (; mbox-short.txt') for in fhand:    if Line.startswith ('from:'):        print(line)

2. Read the file

Use Read () to read the entire file (including line breaks, etc.) and deposit a separate string.

Cases:

>>> Fhand=open ('mbox-short.txt')>>> inp=fhand.read ()  Print(len (INP))print(inp[:20]) from Stephen.marquar

"Python study notes" Coursera's py4e study notes--file