Develop Reference

delete a user defined text from a text file in python

def Delete_con():
contact_to_delete= input("choose name to delete from contact")
to_Delete=list(contact_to_delete)
with open("phonebook1.txt", "r+") as file:
content = file.read()
for line in content:
if not any(line in line for line in to_Delete):
content.write(line)
I get zero error. but the line is not deleted. This function ask the user what name he or she wants to delete from the text file.

This should help.
def Delete_con():
contact_to_delete= input("choose name to delete from contact")
contact_to_delete = contact_to_delete.lower() #Convert input to lower case
with open("phonebook1.txt", "r") as file:
content = file.readlines() #Read lines from text
content = [line for line in content if contact_to_delete not in line.lower()] #Check if user input is in line
with open("phonebook1.txt", "w") as file: #Write back content to text
file.writelines(content)

Assuming that:
you want the user to supply just the name, and not the full 'name:number' pair
your phonebook stores one name:number pair per line
I'd do something like this:
import os
from tempfile import NamedTemporaryFile
def delete_contact():
contact_name = input('Choose name to delete: ')
# You probably want to pass path in as an argument
path = 'phonebook1.txt'
base_dir = os.path.dirname(path)
with open(path) as phonebook, \
NamedTemporaryFile(mode='w+', dir=base_dir, delete=False) as tmp:
for line in phonebook:
# rsplit instead of split supports names containing ':'
# if numbers can also contain ':' you need something smarter
name, number = line.rsplit(':', 1)
if name != contact_name:
tmp.write(line)
os.replace(tmp.name, path)
Using a tempfile like this means that if something goes wrong while processing the file you aren't left with a half-written phonebook, you'll still have the original file unchanged. You're also not reading the entire file into memory with this approach.
os.replace() is Python 3.3+ only, if you're using something older you can use os.rename() as long as you're not using Windows.
Here's the tempfile documentation. In this case, you can think of NamedTemporaryFile(mode='w+', dir=base_dir, delete=False) as something like open('tmpfile.txt', mode='w+'). NamedTemporaryFile saves you from having to find a unique name for your tempfile (so that you don't overwrite an existing file). The dir argument creates the tempfile in the same directory as phonebook1.txt which is a good idea because os.replace() can fail when operating across two different filesystems.

Why is exec() command running with no errors but not producing the expected output?

I'm creating a very basic python program that allows a user to enter a command that is then ran as code.
For example I have imported a file called textScripts.py: within that file there is a function called createFile(). When the user enters textScripts.createFile() it is passed into exec(). It runs without error and exits the program but the file isn't created!
I know the createFile() function works because if I put textScripts.createFile() in the code it creates a file.
Here is the relevant snippet of code:
commandList=[]
while(commandRun):
count = 0
commandList.append(input(">>>"))
exec(commandList[count])
print(commandList[count])
count += 1
here is a screenshot of the code being run:
>>> textScripts.createFile()
>>>
here is a screenshot of the folder:
__pyCache__
textScripts.py
CLIFile.py
there should be a file in this folder
here is the function createFile():
def createFile(
destination = os.path.dirname(__file__),
text = "Sick With the Python\n"
):
''' createFile(destination, text)
This script creates a text file at the
Specified location with a name based on date
'''
date = t.localtime(t.time())
name = "%d_%d_%d.txt" %(date[1], date[2], date[0])
if not(os.path.isfile(destination + name)):
f = open(destination + name, "w")
f.write( text )
f.close
else:
print("file already exists")
I apologize in advance if this is an obvious questions; I'm new to python and have been looking for hours for an answer as to why this happens.

You save file to wrong folder (you can insert "print(destination + name)" in your function)
You need to replace this:
destination + name
to this:
os.path.join(destination, name)
PS:
You don't close the file (f.close -> f.close())
The best way to open any resource is using "with".
For example:
with open('file.txt', 'w') as f:
f.write('line')

new file name each time python run

Using python 2.7..
I am using below to send all print output to a file called output.log. How can i have this send to a different file each time it runs...In bash we could declare a variable called date or something and have that part of the file name...so how can i achieve the same with python ??
So my question is..
every time i run the below script, my file should have a naming convention of output_date/time.log
Also how can i delete file that are older than X days that have a file naming convention of output_*.log
import sys
f = open('output.log', 'w')
sys.stdout = f
print "test"
f.close()

with some personal preference of formatting this is generally what I do.
import time
moment=time.strftime("%Y-%b-%d__%H_%M_%S",time.localtime())
f = open('output'+moment+'.log', 'w')
as far as automated deleting, do you want it deleted on run of the test?
os.remove(fileStringName)
works, you just have to do the arithmetic and string conversion. I would use os.listdir(pathToDirWithOutputLogs) iterate through the file names and do the math on them and call os.remove on the old ones.

To get date/time:
from time import gmtime, strftime
outputFileName = "output_#.log"
outputFileName = outputFileName.replace("#", strftime("%Y-%m-%d_%H:%M:%S", gmtime()))
For numerical incrementing:
outputFileName = "output #.log"
outputVersion = 1
while os.path.isfile(outputFileName.replace("#", str(outputVersion))):
outputVersion += 1
outputFileName = outputFileName.replace("#", str(outputVersion))
To delete files older than a certain date, you can iterate through all the files in the directory with ``, and delete them with os.remove(). You can compare the file names after parsing them.
lastTime = "2015-08-03_19:04:41"
for fn in filter(os.path.isfile, os.listdir()):
strtime = fn[fn.find("_"):fn.rfind(".")]
if strtime < lastTime:
os.remove(fn)

How to open a file of different extension with notepad in python

I have a .fhx file that I could open normally with notepad but I want to open it using Python. I have tried subprocess.popen which I got online but I keep getting errors. I also want to be able to read the contents of this file like a normal text file like how we do in f=open("blah.txt", "r") and f.read(). Could anyone guide me in the right direction ?
import subprocess
filepath = "C:\Users\Ch\Desktop\FHX\fddd.fhx"
notePath = r'C:\Windows\System32\notepad.exe'
subprocess.Popen("%s %s" % (notePath, filepath))

Solved my problem by adding encoding="utf16" to the file open command.
count = 1
filename = r'C:\Users\Ch\Desktop\FHX\27-ESDC_CM02-2.fhx'
f = open(filename, "r", encoding="utf16") #Does not work without encoding
lines = f.read().splitlines()
for line in lines:
if "WIRE SOURCE" in line:
liner = line.split()
if any('SOURCE="INPUT' in s for s in liner):
print(str(count)+") ", "SERIAL INPUT = ", liner[2].replace("DESTINATION=", ""))
count += 1
Now I'm able to get the data the way I wanted.Thanks everyone.

try with shell=True argument
subprocess.call((notePath, filepath), shell=True )

You should be passing a list of args:
import subprocess
filepath = r"C:\Users\Ch\Desktop\FHX\fddd.fhx"
notePath = r'C:\Windows\System32\notepad.exe'
subprocess.check_call([notePath, filepath])
If you want to read the contents then just open the file using open:
with open(r"C:\Users\Ch\Desktop\FHX\fddd.fhx") as f:
for line in f:
print(line)
You need to use raw string for the path also to escape the f n your file path name, if you don't you are going to get errors.
In [1]: "C:\Users\Ch\Desktop\FHX\fddd.fhx"
Out[1]: 'C:\\Users\\Ch\\Desktop\\FHX\x0cddd.fhx'
In [2]: r"C:\Users\Ch\Desktop\FHX\fddd.fhx"
Out[2]: 'C:\\Users\\Ch\\Desktop\\FHX\\fddd.fhx'

Error when trying to read and write multiple files

I modified the code based on the comments from experts in this thread. Now the script reads and writes all the individual files. The script reiterates, highlight and write the output. The current issue is, after highlighting the last instance of the search item, the script removes all the remaining contents after the last search instance in the output of each file.
Here is the modified code:
import os
import sys
import re
source = raw_input("Enter the source files path:")
listfiles = os.listdir(source)
for f in listfiles:
filepath = source+'\\'+f
infile = open(filepath, 'r+')
source_content = infile.read()
color = ('red')
regex = re.compile(r"(\b be \b)|(\b by \b)|(\b user \b)|(\bmay\b)|(\bmight\b)|(\bwill\b)|(\b's\b)|(\bdon't\b)|(\bdoesn't\b)|(\bwon't\b)|(\bsupport\b)|(\bcan't\b)|(\bkill\b)|(\betc\b)|(\b NA \b)|(\bfollow\b)|(\bhang\b)|(\bbelow\b)", re.I)
i = 0; output = ""
for m in regex.finditer(source_content):
output += "".join([source_content[i:m.start()],
"<strong><span style='color:%s'>" % color[0:],
source_content[m.start():m.end()],
"</span></strong>"])
i = m.end()
outfile = open(filepath, 'w+')
outfile.seek(0)
outfile.write(output)
print "\nProcess Completed!\n"
infile.close()
outfile.close()
raw_input()

The error message tells you what the error is:
No such file or directory: 'sample1.html'
Make sure the file exists. Or do a try statement to give it a default behavior.

The reason why you get that error is because the python script doesn't have any knowledge about where the files are located that you want to open.
You have to provide the file path to open it as I have done below. I have simply concatenated the source file path+'\\'+filename and saved the result in a variable named as filepath. Now simply use this variable to open a file in open().
import os
import sys
source = raw_input("Enter the source files path:")
listfiles = os.listdir(source)
for f in listfiles:
filepath = source+'\\'+f # This is the file path
infile = open(filepath, 'r')
Also there are couple of other problems with your code, if you want to open the file for both reading and writing then you have to use r+ mode. More over in case of Windows if you open a file using r+ mode then you may have to use file.seek() before file.write() to avoid an other issue. You can read the reason for using the file.seek() here.