Examples of raw string and Unicode string operators in Python
这篇文章主要介绍了Python原始字符串与Unicode字符串操作符用法,结合实例形式分析了Python针对原始字符与Unicode字符的操作符用法,需要的朋友可以参考下
本文实例讲述了Python原始字符串与Unicode字符串操作符用法。分享给大家供大家参考,具体如下:
#coding=utf8 ''''' 在原始字符串里,所有的字符串都是直接按照字面的意思来使用, 没有转义特殊或不能打印的字符。 正则表达式是一些告诫搜索匹配方式的字符串, 通过是由代表字符、分组、匹配信息、变量名、字符类等的特殊符号组成。 在原始字符串紧靠第一个引号前,需要加上r或R字母,来表示该字符是原始字符串。 原始字符串和普通字符串有这几乎完全相同的语法。 Unicode字符串操作符,大写的U和小写的u是在Python1.6中和Unicode字符串一起被引入的。 它用来把标准字符串或者包含Unicode字符的字符串转换成完全的Unicode字符串对象。 字符串方法和正则表达式引擎也支持Unicode。 Unicode操作符也可以接受原始Unicode字符串,只要将Unicode操作符和原始字符串操作符连接在一起。 注意:Unicode操作符必须出现在原始字符串操作符前面。 ''' import re #原始操作符函数 def originalOper(): #不是原始字符表示换行符 print "\n" #是原始字符表示\n print r"\n" try: #对文件路径加r,不需要对\进行转义 #文件路径中表示斜线 testFile=open(r"E:\PythonDemo\CorePythonBook2\output","r") for line in testFile.readlines(): #通过格式化字符串 #优先使用repr()函数转换为原始字符 line="%r" %line #对匹配模式进行加r处理 #匹配的字符转换为原始字符 m=re.search(r"\\[rn]",line) #字符串中是否包含匹配字符 #如果包含输出该字符串 if m is not None: print line except Exception,e: print e finally: testFile.close() #Unicode操作符函数 def unicodeOper(): print u"abc" print u"\u1234" print u"abc\u1234\n" print ur"Hello\nWorld!" #调用函数 #输出操作原始字符结果 originalOper() #输出Unicode字符串 unicodeOper()
运行结果如下:
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