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
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StringIO的行为与file对象非常像,但它不是磁盘上文件,而是一个内存里的“文件”,我们可以将操作磁盘文件那样来操作StringIO。一个简单的例子,让你对StringIO有一个感性的认识: 1 #coding=gbk 2 3 import StringIO, cStringIO, sys 4 5 s ......
源代码下载:下载地址在这里
# 026
aList = ['1','2','3','4']
aListCopy = aList # 其实,这里仅仅复制了一个引用
del aList[0]
print aList
print aListCopy # 两个引用指向了了同一个对象,所以打印结果一样
aListCopy = aList[:] # 这是复制整个对象的有效方法
del aList[0]
print aList
print aListCopy
......
# 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 ......