(1)去掉所有的特殊字符和标点符号 +(NSString *)deleteCharacters:(NSString *)targetString{if(targetString.length==0|| !targetString) {returnnil; } NSError*error =nil; NSString*pattern =@"[^a-zA-Z0-9\u4e00-\u9fa5]";//正则取反NSRegularExpression *regularExpress = [NSRegularExpression reg...
End of String or Line: $ Start of String Only: \A End of String or Before Ending Newline: \Z Show 5 more Anchors, or atomic zero-width assertions, specify a position in the string where a match must occur. When you use an anchor in your search expression, the regular expression engi...
Recognize line terminators within the string. The default behavior is to match line terminators only at the start and end of the string expression. n: The . character matches line terminators. The default is for . matching to stop at the end of a line. u: Unix-only line endings. ...
A regular expression(简写成RegEx) defines a search pattern for strings. 正则表达式在文本的搜索编辑的场景中很有用处。 RegEx并不是Java发明的,可以说很久很久以前就出现了。1950年代,美国数学家Stephen Cole Kleene提出,后来随着Unix普及开。它从左往右逐个字符扫描文本,找到匹配的模式,继续往下扫描,模式可以使用...
An empty group (that is, subexpression()), matches the space in between characters, including the beginning and end of the subject. Specifying regular expressions in dollar-quoted string constants If you are using a string constant to specify the regular expression for a function, you can use ...
The underscore (_) can be used at the beginning of a regular expression with the same function as the caret (^) or at the end of a regular expression with the same function as the dollar sign ($). _65001_ matches 20 65001 30, 20 65001, 65001 30, 65001, and so on. x|y ...
\A Match only at beginning of string (same as ^). \Z Match only at end of string (same as $). Keyword Matching in Website URL Monitors AlertSite’s keyword matching treats an entire web page as one continuous line of text. Therefore, both the Plain Text and Regular Expression keyw...
The regular expression pattern string includes a backslash to indicate that the dollar symbol is to be interpreted literally rather than as a regular expression anchor. The $ symbol alone would indicate that the regular expression engine should try to begin its match at the end of a string. To...
{n,}Matches at least n repetitions of the previous character or expression.ab{2,}cmatchesabbc,abbbc,abbbbcetc, but notabc Position matching∞ ^Matches the beginning of a line.^meet\.(.*)matches any string that starts withmeet.and places the rest of the string into a group (which could...
Regular expression flags Flag Meaning g Global match: matches across an entire string, rather than stopping at first match i Ignores case m Applies begin and end line special characters (^ and $, respectively) to each line in a multiline string...