每日学习笔记(3)
1,先说说今天体会最深刻的一点:写python代码,一个好的编辑器至关重要,这其中VIM确实是最佳选择。由于python是根据缩进来判断上下文的,因此tab和空格使用不当会害死你的。一段代码在Notepad++里看起来对齐格式没问题,可就是死活编译不过,来到vim下一看,damn it,格式是乱的。本想用4个空格替换掉所有的tab,可该死的Notepad++居然并没有全部替换掉,再换UltraEdit32,依然如故,不得已,最后换了EmEditor,比前面两个强多了,
2,python实现遍历文件夹下所有文件
代码
for root,dirs,files in os.walk(sdir, topdown=False):
for file in files:
full_path = sdir + file
if os.path.exists(full_path) == True:
#process file
for file in files:
full_path = sdir + file
if os.path.exists(full_path) == True:
#process file
3,python处理命令行参数
代码
import sys
import getopt
while true:
try:
opts, args = getopt.getopt(sys.argv[1:], "hs:t:d:i", ["help", "source=", "targe=", "ip="])
for opt, arg in opts:
if opt in ("-h", "--help"):
print("show help info\n")
elif opt in ("-t", "--targe"):
target = arg
elif opt in ("-s", "--source"):
source = arg
elif opt in("-e", "--exit"):
sys.exit(0)
except getopt.GetoptError:
sys.exit(-1)
import getopt
while true:
try:
opts, args = getopt.getopt(sys.argv[1:], "hs:t:d:i", ["help", "source=", "targe=", "ip="])
for opt, arg in opts:
if opt in ("-h", "--help"):
print("show help info\n")
elif opt in ("-t", "--targe"):
target = arg
elif opt in ("-s", "--source"):
source = arg
elif opt in("-e", "--exit"):
sys.exit(0)
except getopt.GetoptError:
sys.exit(-1)
4,python中的信号处理机制
代码
import signal
def handler(signum, frame):
print 'Signal handler called with signal', signum
raise TimeOutError, "TimeOut!"
try:
# Set the signal handler and a 1-second alarm
signal.signal(signal.SIGALRM, handler)
signal.alarm(1)
# This while loop hang indefinitely
while True:
print 'a',
signal.alarm(0) # Disable the alarm
except:
print
print 'Time out caught!'
def handler(signum, frame):
print 'Signal handler called with signal', signum
raise TimeOutError, "TimeOut!"
try:
# Set the signal handler and a 1-second alarm
signal.signal(signal.SIGALRM, handler)
signal.alarm(1)
# This while loop hang indefinitely
while True:
print 'a',
signal.alarm(0) # Disable the alarm
except:
print 'Time out caught!'
5,mysql的几个常用点:1)truncate table tablename用来删除表中所有数据。2)limit相当于其他数据库中的top,取指定条数记录。3)desc 表名用来查看表结构 4)若表中字段是关键字,例如group,那么需要使用`group`(不是单引号,是数字1旁边那个键)。
作者:洞庭散人
出处:http://phinecos.cnblogs.com/
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posted on 2010-04-29 20:47 Phinecos(洞庭散人) 阅读(810) 评论(0) 编辑 收藏 举报