Python入门的36个例子 之 33
源代码下载：下载地址在这里
# 037
fileName = ''
while 1:
fileName = raw_input("Input a file name:")
if fileName == 'q':
break
try:
f = file(fileName, 'r')
print 'Opened a file.'
except:
print 'There is no file named', fileName
# end of try and except
f.close()
# end of while
output：
Input a file name:haha
There is no file named haha
Input a file name:txt
There is no file named txt
Input a file name:1
There is no file named 1
Input a file name:037_Exception.py
Opened a file.
Input a file name:q
相关文档：
二元运算符及其对应的特殊方法
二元运算符
特殊方法
+
__add__,__radd__
-
__sub__,__rsub__
*
__mul__,__rmul__
/
__div__,__rdiv__,__truediv__,__rtruediv__
//
__floordiv__,__rfloordiv__
%
__mod__,__rmod__
**
__pow__,__rpow__
<<
__lshift__,__rlshift__
>>
_ ......
源代码下载：下载地址在这里
# 022
listNum1 = [1, 3]
listNum2 = [2, 4]
listStr1 = ['a', 'c']
listStr2 = ['b', 'd']
# 列表的合并
list1 = listNum1 + listStr1
for ele in list1:
print ele
print '\n'
# 判断列表中是否包含某元素
print 'b' in list1
print 1 in list1
# 删除某个元素
for ele in ......
源代码下载：下载地址在这里
# 034
class Person:
def __init__(self, name):
self.name = name # 这一句中第一个name是类中包含的域，第二个name是传进来的参数
# end of def
def sayHello(self):
print 'Hello!'
# end of def
# end of class
p = Person('Ning')
print p.nam ......
源代码下载：下载地址在这里
# 035
class Person:
population = 0 #这个变量是属于整个类的
def __init__(self, name):
self.name = name
print '初始化 %s' % self.name
Person.population += 1
# end of def
def __del__(self):
print '%s says bye.' % self. ......
