Zero or one of a a? Zero or more of a a* One or more of a a+ Exactly 3 of a a{3} 3 or more of a a{3,} Between 3 and 6 of a a{3,6} Start of string ^ End of string $ A word boundary \b Non-word boundary
序列 prog=re.compile(pattern)result=prog.match(string) 等价于 result=re.match(pattern,string) 如果需要多次使用这个正则表达式的话,使用re.compile()和保存这个正则对象以便复用,可以让程序更加高效。 注解 通过re.compile()编译后的样式,和模块级的函数会被缓存, 所以少数的正则表达式使用无需考虑编译的问题。
match(pattern, string, flags=0) Try to apply the pattern at the start of the string, returning a match object, or None if no match was found. search(pattern, string, flags=0) Scan through string looking for a match to the pattern, returning a match object, or None if no match was ...
match("dog") # No match as "o" is not at the start of "dog". >>> pattern.match("dog", 1) # Match as "o" is the 2nd character of "dog". <re.Match object; span=(1, 2), match='o'> 如果你想定位匹配在 string 中的位置,使用 search() 来替代(另参考 search() vs. match(...
Start of string ^ End of string $ A word boundary \b Non-word boundary \B Regular Expression 5 matches (156 steps, 5.5ms) / (?<=[a-zA-Z])(?=[A-Z]) / g Test String thisIsACamelCaseString 1:23 Substitution Processing... thisIsACamelCaseString 1:1...
In general, the caret symbol represents the start of the string, but when it is typed after the opening square bracket it negates the character set. For example, the regular expression[^c]armeans: any character exceptc, followed by the charactera, followed by the letterr. ...
usingSystem;usingSystem.Text.RegularExpressions;publicclassExample{publicstaticvoidMain(){stringpattern =@"\b[at]\w+";stringtext ="The threaded application ate up the thread pool as it executed."; MatchCollection matches; Regex defaultRegex =newRegex(pattern);// Get matches of pattern in textmatc...
Replace(String, String) In a specified input string, replaces all strings that match a regular expression pattern with a specified replacement string. Replace(String, MatchEvaluator, Int32) In a specified input string, replaces a specified maximum number of strings that match a regular expressi...
String timeElasped=sec2DHMS((endTime - startTime)/1000); log.info("#"+tbSN+" End. "+count+" records have been inserted to '"+tableName+"'.( time elapsed: " + timeElasped +")");///manager.reportFinished(String.valueOf(tbSN), tableName, timeElasped); ...
usingSystem;usingSystem.Text.RegularExpressions;publicclassExample{publicstaticvoidMain(){stringpattern =@"\b[at]\w+";stringtext ="The threaded application ate up the thread pool as it executed."; MatchCollection matches; Regex defaultRegex =newRegex(pattern);// Get matches of pattern in textmatc...