mirror of
https://github.com/rasbt/python_reference.git
synced 2024-11-24 04:21:15 +00:00
45 lines
1.0 KiB
Python
Executable File
45 lines
1.0 KiB
Python
Executable File
# Different methods to read from text files
|
|
# sr 11/18/2013
|
|
# Python 3.x
|
|
|
|
# Note: rb opens file in binary mode to avoid issues with Windows systems
|
|
# where '\r\n' is used instead of '\n' as newline character(s).
|
|
|
|
|
|
# A) Reading in Byte chunks
|
|
reader_a = open("file.txt", "rb")
|
|
chunks = []
|
|
data = reader_a.read(64) # reads first 64 bytes
|
|
while data != "":
|
|
chunks.append(data)
|
|
data = reader_a.read(64)
|
|
if data:
|
|
chunks.append(data)
|
|
print (len(chunks))
|
|
reader_a.close()
|
|
|
|
|
|
# B) Reading whole file at once into a list of lines
|
|
with open("file.txt", "rb") as reader_b: # recommended syntax, auto closes
|
|
data = reader_b.readlines() # data is assigned a list of lines
|
|
print (len(data))
|
|
|
|
|
|
# C) Reading whole file at once into a string
|
|
with open("file.txt", "rb") as reader_c:
|
|
data = reader_c.read() # data is assigned a list of lines
|
|
print (len(data))
|
|
|
|
|
|
# D) Reading line by line into a list
|
|
data = []
|
|
with open("file.txt", "rb") as reader_d:
|
|
for line in reader_d:
|
|
data.append(line)
|
|
print (len(data))
|
|
|
|
|
|
|
|
|
|
|