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

http://code.activestate.com/recipes/168639-progress-bar-class/ (2002) http://code.activestate.com/recipes/299207-console-text-progress-indicator-class/ (2004) http://pypi.python.org/pypi/progressbar (2006)

还有很多教程等着你去谷歌。

其他回答

我写了一个简单的进度条:

def bar(total, current, length=10, prefix="", filler="#", space=" ", oncomp="", border="[]", suffix=""):
    if len(border) != 2:
        print("parameter 'border' must include exactly 2 symbols!")
        return None

    print(prefix + border[0] + (filler * int(current / total * length) +
                                      (space * (length - int(current / total * length)))) + border[1], suffix, "\r", end="")
    if total == current:
        if oncomp:
            print(prefix + border[0] + space * int(((length - len(oncomp)) / 2)) +
                  oncomp + space * int(((length - len(oncomp)) / 2)) + border[1], suffix)
        if not oncomp:
            print(prefix + border[0] + (filler * int(current / total * length) +
                                        (space * (length - int(current / total * length)))) + border[1], suffix)

正如你所看到的,它有:条的长度,前缀和后缀,填充,空间,文本在条上100%(oncomp)和边界

这里有一个例子:

from time import sleep, time
start_time = time()
for i in range(10):
    pref = str((i+1) * 10) + "% "
    complete_text = "done in %s sec" % str(round(time() - start_time))
    sleep(1)
    bar(10, i + 1, length=20, prefix=pref, oncomp=complete_text)

正在进行中:

30% [######              ]

Out on complete:

100% [   done in 9 sec   ] 

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%

试试由Python界的莫扎特Armin Ronacher编写的点击库。

$ pip install click # both 2 and 3 compatible

创建一个简单的进度条:

import click

with click.progressbar(range(1000000)) as bar:
    for i in bar:
        pass 

这是它的样子:

# [###-------------------------------]    9%  00:01:14

定制您心中的内容:

import click, sys

with click.progressbar(range(100000), file=sys.stderr, show_pos=True, width=70, bar_template='(_(_)=%(bar)sD(_(_| %(info)s', fill_char='=', empty_char=' ') as bar:
    for i in bar:
        pass

自定义:

(_(_)===================================D(_(_| 100000/100000 00:00:02

还有更多的选项,请参阅API文档:

 click.progressbar(iterable=None, length=None, label=None, show_eta=True, show_percent=None, show_pos=False, item_show_func=None, fill_char='#', empty_char='-', bar_template='%(label)s [%(bar)s] %(info)s', info_sep=' ', width=36, file=None, color=None)

写入一个\r到控制台。这是一个“回车”,它使它之后的所有文本都在行首回显。喜欢的东西:

def update_progress(progress):
    print '\r[{0}] {1}%'.format('#'*(progress/10), progress)

这将给你一些像:[##########]100%

对于python 3:

def progress_bar(current_value, total):
    increments = 50
    percentual = ((current_value/ total) * 100)
    i = int(percentual // (100 / increments ))
    text = "\r[{0: <{1}}] {2}%".format('=' * i, increments, percentual)
    print(text, end="\n" if percentual == 100 else "")