如何一遍又一遍地循环，直到我们停止或暂停它

Question

我最近在这里问了一个问题how can I read each line of a xls file with pausing，我得到的答案解决了我的问题。代码如下

import time
import pandas as pd
import os
import xlrd
# at first I try to know how many rows and how many columns I have 
workbook = xlrd.open_workbook('myfile.xls')
for sheet in workbook.sheets():
    for row in range(sheet.nrows):
        for column in range(sheet.ncols):
            os.system('clear')
            print "value::: ", sheet.cell(row,column).value
            time.sleep(5.5)    # pause 5.5 seconds

我想要做的是以某种方式制作循环，使其到达 xls 行的末尾，然后一遍又一遍地返回开头，直到我停止它或有时暂停它，你知道怎么做吗？去做这个 ？

Answer 1

只需将它放在另一个循环中。例如，如果您想将整个事情重复 10 次，只需这样做：

for i in xrange(10):    
    for sheet in workbook.sheets():
        num_of_cells = sheet.nrows * sheet.ncols
        for cell in range(num_of_cells):
            row = int(cell / sheet.ncols)
            col = cell % sheet.ncols
            print "value::: ", sheet.cell(row, col).value
            time.sleep(5.5)    # pause 5.5 seconds

Answer 2

我发现的最简单的方法可能是使用python 的KeyboardInterrupt 异常 - 当然，如果您可以在结束循环时停止整个脚本（通过按 Ctrl-C )。

for sheet in workbook.sheets():
    for row in range(sheet.nrows):
        for column in range(sheet.ncols):
            try:
                os.system('clear')
                print "value::: ", sheet.cell(row,column).value
                time.sleep(5.5)    # pause 5.5 seconds
            except KeyboardInterrupt:
                pass #insert here anything you'd like your script to do before it halts