process_bar = ShowProcess(max_steps) # 1.在循環(huán)前定義類的實體， max_steps是總的步數(shù)
for i in range(max_steps + 1):
  process_bar.show_process()   # 2.顯示當前進度
  time.sleep(0.05)
process_bar.close('done')      # 3.處理結束后顯示消息

#!/usr/local/lib
# -*- coding: UTF-8 -*-
import sys, time
class ShowProcess():
  """
  顯示處理進度的類
  調(diào)用該類相關函數(shù)即可實現(xiàn)處理進度的顯示
  """
  i = 0 # 當前的處理進度
  max_steps = 0 # 總共需要處理的次數(shù)
  max_arrow = 50 #進度條的長度
  # 初始化函數(shù)，需要知道總共的處理次數(shù)
  def __init__(self, max_steps):
    self.max_steps = max_steps
    self.i = 0
  # 顯示函數(shù)，根據(jù)當前的處理進度i顯示進度
  # 效果為[>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>]100.00%
  def show_process(self, i=None):
    if i is not None:
      self.i = i
    else：
      self.i += 1
    num_arrow = int(self.i * self.max_arrow / self.max_steps) #計算顯示多少個'>'
    num_line = self.max_arrow - num_arrow #計算顯示多少個'-'
    percent = self.i * 100.0 / self.max_steps #計算完成進度，格式為xx.xx%
    process_bar = '[' + '>' * num_arrow + '-' * num_line + ']'\
           + '%.2f' % percent + '%' + '\r' #帶輸出的字符串，'\r'表示不換行回到最左邊
    sys.stdout.write(process_bar) #這兩句打印字符到終端
    sys.stdout.flush()
  def close(self, words='done'):
    print ''
    print words
    self.i = 0
if __name__=='__main__':
  max_steps = 100
  process_bar = ShowProcess(max_steps)
  for i in range(max_steps + 1):
    process_bar.show_process()
    time.sleep(0.05)
  process_bar.close()

[>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>]100.00%
done