如果你正在开发一个命令行界面，我建议你看看click，它非常好:

import click
import time

for filename in range(3):
    with click.progressbar(range(100), fill_char='=', empty_char=' ') as bar:
        for user in bar:
            time.sleep(0.01)

下面是你得到的输出:

$ python test.py
  [====================================]  100%
  [====================================]  100%
  [=========                           ]   27%

使用@Mark-Rushakoff的答案，我想出了一个更简单的方法，不需要调用sys库。它适用于Python 3。Windows测试:

from time import sleep
for i in range(21):
    # the exact output you're looking for:
    print ("\r[%-20s] %d%%" % ('='*i, 5*i), end='')
    sleep(0.25)

你可以使用\r(回车)。演示:

import sys
total = 10000000
point = total / 100
increment = total / 20
for i in xrange(total):
    if(i % (5 * point) == 0):
        sys.stdout.write("\r[" + "=" * (i / increment) +  " " * ((total - i)/ increment) + "]" +  str(i / point) + "%")
        sys.stdout.flush()

在这里你可以使用以下代码作为函数:

def drawProgressBar(percent, barLen = 20):
    sys.stdout.write("\r")
    progress = ""
    for i in range(barLen):
        if i < int(barLen * percent):
            progress += "="
        else:
            progress += " "
    sys.stdout.write("[ %s ] %.2f%%" % (progress, percent * 100))
    sys.stdout.flush()

使用.format:

def drawProgressBar(percent, barLen = 20):
    # percent float from 0 to 1. 
    sys.stdout.write("\r")
    sys.stdout.write("[{:<{}}] {:.0f}%".format("=" * int(barLen * percent), barLen, percent * 100))
    sys.stdout.flush()

我发现有用的库tqdm (https://github.com/tqdm/tqdm/，以前是:https://github.com/noamraph/tqdm)。它可以自动估计完成时间，也可以用作迭代器。

用法:

import tqdm
import time

for i in tqdm.tqdm(range(1000)):
    time.sleep(0.01)
    # or other long operations

结果:

|####------| 450/1000  45% [elapsed: 00:04 left: 00:05, 99.15 iters/sec]

TQDM可以包装任何可迭代对象。

在这里和其他地方的一些答案的基础上，我编写了这个简单的函数，它显示一个进度条和经过/估计的剩余时间。应该在大多数基于unix的机器上运行。

import time
import sys

percent = 50.0
start = time.time()
draw_progress_bar(percent, start)


def draw_progress_bar(percent, start, barLen=20):
sys.stdout.write("\r")
progress = ""
for i in range(barLen):
    if i < int(barLen * percent):
        progress += "="
    else:
        progress += " "

elapsedTime = time.time() - start;
estimatedRemaining = int(elapsedTime * (1.0/percent) - elapsedTime)

if (percent == 1.0):
    sys.stdout.write("[ %s ] %.1f%% Elapsed: %im %02is ETA: Done!\n" % 
        (progress, percent * 100, int(elapsedTime)/60, int(elapsedTime)%60))
    sys.stdout.flush()
    return
else:
    sys.stdout.write("[ %s ] %.1f%% Elapsed: %im %02is ETA: %im%02is " % 
        (progress, percent * 100, int(elapsedTime)/60, int(elapsedTime)%60,
         estimatedRemaining/60, estimatedRemaining%60))
    sys.stdout.flush()
    return