问题:如何在控制台的同一位置写入输出?
我是python的新手,正在编写一些脚本来自动从FTP服务器等下载文件。我想显示下载进度,但是我希望它保持不变,例如:
输出:
正在下载文件FooFile.txt [47%]
我正在尝试避免这样的事情:
Downloading File FooFile.txt [47%]
Downloading File FooFile.txt [48%]
Downloading File FooFile.txt [49%]
我应该怎么做呢?
复制: 如何在命令行应用程序的当前行上打印?
I am new to python and am writing some scripts to automate downloading files from FTP servers, etc. I want to show the progress of the download, but I want it to stay in the same position, such as:
output:
Downloading File FooFile.txt [47%]
I’m trying to avoid something like this:
Downloading File FooFile.txt [47%]
Downloading File FooFile.txt [48%]
Downloading File FooFile.txt [49%]
How should I go about doing this?
Duplicate: How can I print over the current line in a command line application?
回答 0
您还可以使用回车符:
sys.stdout.write("Download progress: %d%% \r" % (progress) )
sys.stdout.flush()
You can also use the carriage return:
sys.stdout.write("Download progress: %d%% \r" % (progress) )
sys.stdout.flush()
回答 1
Python 2
我喜欢以下内容:
print 'Downloading File FooFile.txt [%d%%]\r'%i,
演示:
import time
for i in range(100):
time.sleep(0.1)
print 'Downloading File FooFile.txt [%d%%]\r'%i,
Python 3
print('Downloading File FooFile.txt [%d%%]\r'%i, end="")
演示:
import time
for i in range(100):
time.sleep(0.1)
print('Downloading File FooFile.txt [%d%%]\r'%i, end="")
带有Python 3的PyCharm调试器控制台
# On PyCharm Debugger console, \r needs to come before the text.
# Otherwise, the text may not appear at all, or appear inconsistently.
# tested on PyCharm 2019.3, Python 3.6
import time
print('Start.')
for i in range(100):
time.sleep(0.02)
print('\rDownloading File FooFile.txt [%d%%]'%i, end="")
print('\nDone.')
Python 2
I like the following:
print 'Downloading File FooFile.txt [%d%%]\r'%i,
Demo:
import time
for i in range(100):
time.sleep(0.1)
print 'Downloading File FooFile.txt [%d%%]\r'%i,
Python 3
print('Downloading File FooFile.txt [%d%%]\r'%i, end="")
Demo:
import time
for i in range(100):
time.sleep(0.1)
print('Downloading File FooFile.txt [%d%%]\r'%i, end="")
PyCharm Debugger Console with Python 3
# On PyCharm Debugger console, \r needs to come before the text.
# Otherwise, the text may not appear at all, or appear inconsistently.
# tested on PyCharm 2019.3, Python 3.6
import time
print('Start.')
for i in range(100):
time.sleep(0.02)
print('\rDownloading File FooFile.txt [%d%%]'%i, end="")
print('\nDone.')
回答 2
使用类似于curses模块的终端处理库:
curses模块提供了curses库的接口,curses库是便携式高级终端处理的实际标准。
Use a terminal-handling library like the curses module:
The curses module provides an interface to the curses library, the de-facto standard for portable advanced terminal handling.
回答 3
Print the backspace character \b
several times, and then overwrite the old number with the new number.
回答 4
#kinda like the one above but better :P
from __future__ import print_function
from time import sleep
for i in range(101):
str1="Downloading File FooFile.txt [{}%]".format(i)
back="\b"*len(str1)
print(str1, end="")
sleep(0.1)
print(back, end="")
#kinda like the one above but better :P
from __future__ import print_function
from time import sleep
for i in range(101):
str1="Downloading File FooFile.txt [{}%]".format(i)
back="\b"*len(str1)
print(str1, end="")
sleep(0.1)
print(back, end="")
回答 5
对于Python 3xx:
import time
for i in range(10):
time.sleep(0.2)
print ("\r Loading... {}".format(i)+str(i), end="")
For Python 3xx:
import time
for i in range(10):
time.sleep(0.2)
print ("\r Loading... {}".format(i)+str(i), end="")
回答 6
一个对我有用的整洁的解决方案是:
from __future__ import print_function
import sys
for i in range(10**6):
perc = float(i) / 10**6 * 100
print(">>> Download is {}% complete ".format(perc), end='\r')
sys.stdout.flush()
print("")
这个sys.stdout.flush
很重要,否则它真的很笨拙,print("")
on for循环退出也很重要。
更新:如评论中所述,print
也有一个flush
参数。因此,以下内容也将起作用:
from __future__ import print_function
for i in range(10**6):
perc = float(i) / 10**6 * 100
print(">>> Download is {}% complete ".format(perc), end='\r', flush=True)
print("")
A neat solution that has been working for me is:
from __future__ import print_function
import sys
for i in range(10**6):
perc = float(i) / 10**6 * 100
print(">>> Download is {}% complete ".format(perc), end='\r')
sys.stdout.flush()
print("")
The sys.stdout.flush
is important otherwise it gets really clunky and the print("")
on for loop exit is also important.
UPDATE: As mentioned in the comments, print
also has a flush
argument. So the following will also work:
from __future__ import print_function
for i in range(10**6):
perc = float(i) / 10**6 * 100
print(">>> Download is {}% complete ".format(perc), end='\r', flush=True)
print("")
回答 7
x="A Sting {}"
for i in range(0,1000000):
y=list(x.format(i))
print(x.format(i),end="")
for j in range(0,len(y)):
print("\b",end="")
x="A Sting {}"
for i in range(0,1000000):
y=list(x.format(i))
print(x.format(i),end="")
for j in range(0,len(y)):
print("\b",end="")