Python入门的36个例子 之 35
源代码下载：下载地址在这里
# 039
while True:
try:
x = int(raw_input('Input a number:'))
y = int(raw_input('Input a number:'))
z = x / y
except ValueError, ev:
print 'That is not a valid number.', ev
except ZeroDivisionError, ez:
print 'Divisor is zero:', ez
except:
print 'Unexpected error.'
raise
else:
print 'There is no error.'
break
# end of try
# end of while
print x,'/',y,'=',x/y
output：
Input a number:w
That is not a valid number. invalid literal for int() with base 10: 'w'
Input a number:9
Input a number:0
Divisor is zero: integer division or modulo by zero
Input a number:9
Input a number:3
There is no error.
9 / 3 = 3
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# 004
# 利用三引号(''' or """)可以指示多行字符串
print '''line1
line2
line3'''
# 另外，你还可以在三引号中任意使用单引号和双引号
print ''' "What's up? ," he replied.'''
# 否则，你好使用转义符来实现同样的效果
# 还是使用三引号好，不然就破坏了视觉美了
print ' \"Wha ......
源代码下载：下载地址在这里
# 023
# Tuple(元素组)是不可变的列表
tuple1 = (1, 2, 3)
print tuple1
tuple2 = (tuple1, 4, 5, 6) # 一个元素组可以作为另外一个元素组的元素
print tuple2 # 并且能够在存储的时候保持原始的逻辑关系
for ele in tuple2:
print ele
print '\n'
for ele in tuple2[0]:
pr ......
源代码下载：下载地址在这里
# 025
# 序列的神奇之处在于你可以使用相同的方式tuple、list和string
se = ['a', 'b', 'c', 'd']
li = ['a', 'b', 'c', 'd']
tu = ('a', 'b', 'c', 'd')
string = 'abcd'
print se[1]
print li[1]
print tu[1]
print string[1]
# 序列的另外一个神奇之处在于，你可以使用负数进行索 ......
# 027
toolName = 'Google'
if toolName.startswith('Go'):
print 'The tool\'s name starts with \"Go\".'
if 'oo' in toolName:
print 'The tool\'s name contains the stirng "oo".'
print toolName.find('gl') # 返回首次出现“gl”字符串的索引
if toolName.find('Baidu ......
