目的

　　获得一个首尾不含多余空格的字符串

方法

可以使用字符串的以下方法处理：

string.lstrip(s[, chars])
Return a copy of the string with leading characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the beginning of the string this method is called on.

string.rstrip(s[, chars])
Return a copy of the string with trailing characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the end of the string this method is called on.

string.strip(s[, chars])
Return a copy of the string with leading and trailing characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the both ends of the string this method is called on.

具体的效果如下：
复制代码 代码如下:
In [10]: x='     Hi,Jack!        '

In [11]: print '|',x.lstrip(),'|',x.rstrip(),'|',x.strip(),'|'
| Hi,Jack!         |      Hi,Jack! | Hi,Jack! |

其中提供的参数chars用来删除特定的符号，注意空格并没有被移除，例如：
复制代码 代码如下:
In [12]: x='yxyxyxxxyy Hello xyxyxyy'

In [13]: print x.strip('xy')
 Hello