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Python file.readline(2) reads first 2 charectars


Python file.readline(2) reads first 2 charectars

By : Thanh Cả Phan
Date : November 22 2020, 03:01 PM
this will help Use getUserNumber = file.readlines()[1] instead.
readline reads the next line, and the arg is how many characters to read, so previously you were reading the first two characters of the first line.
code :


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Python readline - reads only first line

Python readline - reads only first line


By : Michiel Prins
Date : March 29 2020, 07:55 AM
I wish did fix the issue. When you call open you are opening the file anew and starting from the first line. Every time you call readline on an already open file it moves its internal "pointer" to the start of the next line. However, if you re-open the file the "pointer" is also re-initialized - and when you call readline it reads the first line again.
Imagine that open returned a file object that looked like this:
code :
class File(object):
    """Instances of this class are returned by `open` (pretend)"""

    def __init__(self, filesystem_handle):
        """Called when the file object is initialized by `open`"""

        print "Starting up a new file instance for {file} pointing at position 0.".format(...)

        self.position = 0
        self.handle = filesystem_handle


    def readline(self):
        """Read a line. Terribly naive. Do not use at home"

        i = self.position
        c = None
        line = ""
        while c != "\n":
            c = self.handle.read_a_byte()
            line += c

        print "Read line from {p} to {end} ({i} + {p})".format(...)

        self.position += i
        return line
Starting up a new file instance for /my-textfile.txt pointing at position 0.
Read line from 0 to 80 (80 + 0)
Read line from 80 to 160 (80 + 80)
Starting up a new file instance for /my-textfile.txt pointing at position 0.
Read line from 0 to 80 (80 + 0)
Starting up a new file instance for /my-textfile.txt pointing at position 0.
Read line from 0 to 80 (80 + 0)
Using StreamReader.ReadLine in loop only reads one line from text file

Using StreamReader.ReadLine in loop only reads one line from text file


By : sonal
Date : March 29 2020, 07:55 AM
it should still fix some issue Unless you have a specific need to go through the rigmarole of using StreamReader, I suggest using File.ReadAllLines(), which returns an (enumerable) string array.
Better yet, use linq :-)
code :
System.Console.WriteLine("users.ul exists: " + File.Exists("users.ul"));

// Check the status of users.ul. If it exists, fill the user dictionary with its data.
if (File.Exists("users.ul")) {
    var lines = File.ReadAllLines("users.ul");
    // Usernames are listed first in users.ul, and are followed by a period
    // and then the password associated with that username.
    var users = lines.Select(o => o.Split('.'))
                     .Where(o => o.Length == 2)
                     .Select(o => new User(o[0].Trim(), o[1].Trim());

    System.Console.WriteLine("count: " + users.Count());
}
readline() reads all data including '\n'

readline() reads all data including '\n'


By : Coding Jam
Date : March 29 2020, 07:55 AM
With these it helps This looks like a platform issue. It appears your terminal, Python interpreter and paste source disagree on what an end of line is; by the presence of "D:" in the path, I guess it's a Windows platform, where newlines are traditionally stored as '\r\n' and entered as '\r' (carriage return). Python follows the C/Unix tradition of processing newlines as '\n' (line feed). With the wrong combination of terminal handling and clipboard contents, the '\n' character will be passed like any other and not end a line. You can experiment with entering the newline styles manually; carriage return is Ctrl+M and line feed is Ctrl+J. Python also does have support for different newline styles; my guess is that in your particular terminal, sys.stdin is opened with '\r' newlines.
ReadLine() reads only once

ReadLine() reads only once


By : user3635682
Date : March 29 2020, 07:55 AM
I wish did fix the issue. You want to call AcceptTcpClient from your background worker, so your UI thread is not stuck while you are waiting for the client to connect.
You should only call GetStream() once; save the result as a Stream object and you can get both the reader and writer from it.
Streamreader.readLine reads lines through one

Streamreader.readLine reads lines through one


By : 孟祥冰
Date : March 29 2020, 07:55 AM
it fixes the issue Even-numbered rows appear skipped because each iteration of the loop calls ReadLine twice:
The first call is in the header of the loop The second call is in the body, on the assignment line
code :
string lastLine;
while ((lastLine = file.ReadLine()) != null)
{
    rows[count] = lastLine;
    count++;
}
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