我编写了一个简单的控制台应用程序,使用ftplib从FTP服务器上传和下载文件。

我想应用程序显示一些可视化的下载/上传进度为用户;每次下载数据块时,我希望它提供一个进度更新,即使它只是一个数字表示,如百分比。

重要的是,我想避免擦除之前打印到控制台的所有文本(即,我不想在打印更新的进度时“清除”整个终端)。

这似乎是一个相当常见的任务——我如何才能制作一个进度条或类似的可视化输出到我的控制台,同时保留之前的程序输出?


当前回答

把我在这里找到的一些想法放在一起,加上估计的剩余时间:

import datetime, sys

start = datetime.datetime.now()

def print_progress_bar (iteration, total):

    process_duration_samples = []
    average_samples = 5

    end = datetime.datetime.now()

    process_duration = end - start

    if len(process_duration_samples) == 0:
        process_duration_samples = [process_duration] * average_samples

    process_duration_samples = process_duration_samples[1:average_samples-1] + [process_duration]
    average_process_duration = sum(process_duration_samples, datetime.timedelta()) / len(process_duration_samples)
    remaining_steps = total - iteration
    remaining_time_estimation = remaining_steps * average_process_duration

    bars_string = int(float(iteration) / float(total) * 20.)
    sys.stdout.write(
        "\r[%-20s] %d%% (%s/%s) Estimated time left: %s" % (
            '='*bars_string, float(iteration) / float(total) * 100,
            iteration,
            total,
            remaining_time_estimation
        ) 
    )
    sys.stdout.flush()
    if iteration + 1 == total:
        print 


# Sample usage

for i in range(0,300):
    print_progress_bar(i, 300)

其他回答

Tqdm:在你的循环中添加一个进度表:

>>> import time
>>> from tqdm import tqdm
>>> for i in tqdm(range(100)):
...     time.sleep(1)
... 
|###-------| 35/100  35% [elapsed: 00:35 left: 01:05,  1.00 iters/sec]

下面是一个用Python编写的进度条的好例子:http://nadiana.com/animated-terminal-progress-bar-in-python

但如果你想自己写。你可以使用curses模块让事情变得更简单:)

(编辑) 也许更容易不是诅咒这个词。但是如果你想创建一个成熟的cui,那么curses会为你照顾很多东西。

(编辑) 由于旧的链接已经失效,我已经发布了我自己的Python Progressbar版本,请在这里获取:https://github.com/WoLpH/python-progressbar

根据上面的答案和其他类似的关于CLI进度条的问题,我想我得到了一个普遍的答案。请登录https://stackoverflow.com/a/15860757/2254146查看。

总之,代码是这样的:

import time, sys

# update_progress() : Displays or updates a console progress bar
## Accepts a float between 0 and 1. Any int will be converted to a float.
## A value under 0 represents a 'halt'.
## A value at 1 or bigger represents 100%
def update_progress(progress):
    barLength = 10 # Modify this to change the length of the progress bar
    status = ""
    if isinstance(progress, int):
        progress = float(progress)
    if not isinstance(progress, float):
        progress = 0
        status = "error: progress var must be float\r\n"
    if progress < 0:
        progress = 0
        status = "Halt...\r\n"
    if progress >= 1:
        progress = 1
        status = "Done...\r\n"
    block = int(round(barLength*progress))
    text = "\rPercent: [{0}] {1}% {2}".format( "#"*block + "-"*(barLength-block), progress*100, status)
    sys.stdout.write(text)
    sys.stdout.flush()

看起来像

百分比:[##########]99.0%

写入'\r'将把光标移回行首。

这将显示一个百分比计数器:

import time
import sys

for i in range(100):
    time.sleep(1)
    sys.stdout.write("\r%d%%" % i)
    sys.stdout.flush()

函数从Greenstick 2.7:

def printProgressBar (iteration, total, prefix = '', suffix = '',decimals = 1, length = 100, fill = '#'):

percent = ("{0:." + str(decimals) + "f}").format(100 * (iteration / float(total)))
filledLength = int(length * iteration // total)
bar = fill * filledLength + '-' * (length - filledLength)
print'\r%s |%s| %s%% %s' % (prefix, bar, percent, suffix),
sys.stdout.flush()
# Print New Line on Complete                                                                                                                                                                                                              
if iteration == total:
    print()