(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NS
public static void main(String[] args) { //在这个字符串:dfsdfsd43324,是否符合指定的正则表达式:\w+ //表达式对象 Pattern pattern = Pattern.compile("\\w+"); //创建Matcher对象 Matcher matcher = pattern.matcher("dfsdfsd&&43324");//尝试将整个字符串序列与该模式匹配 //boolean yesno = matche...
re模块 re=regular expression 1 import re re方法一:根据规则查找/提取内容 1 re.findall(查找规则,匹配内容) 返回结构化数据,两个参数,形式参数为pattern(规律)string(需要查找/匹配的字符串) re方法二:根据规则匹配/验证内容 1 re.match(匹配规则,匹配内容) 返回布尔,两个参数,形式参数为pattern(规律...
If you are using a string constant to specify the regular expression for a function, you can use adollar-quoted string constantto avoidescaping the backslash characters in the regular expression. (If you are usingsingle-quoted string constants, you need to escape the backslashes.) ...
Principle 2: In an alternationa|b|c..., the leftmost alternative that allows a match for the whole regular expression will be the one used. Principle 3: The maximal matching quantifiers?,*,+, and{n,m}will in general match as much of the string as possible while still allowing the whol...
You can use regular expressions to describe a set of strings based on common characteristics shared by each string in the set. A regular expression is basically a sequence of characters that defines a search pattern, which is used for pattern matching. Regular expressions vary in complexity, but...
Any other character appearing in a regular expression is ordinary, unless a\precedes it. Special characters serve a special purpose. For instance, the.matches anything except a new line. A regular expression likes.nmatches any three-character string that begins withsand ends withn, includingsunand...
Three filtering modes are provided for commands that support regular expressions. | begin regular-expression: displays all the lines beginning with the line that matches the regular expression. Filter the character strings to be entered until the specified case-sensitive character string is displayed. ...
Regex 正则表达式(Regular expression):outline:1.常用re flag参数 2.常用re function 3.当匹配成功时返回一个对象 4. Quantifier 5.Character Classes 6.Negative Character Class 7. Word Boundary Anchor 8. Be…
Use String class methods such asindexOf(),substr(), orsubstring()instead of regular expressions for basic string finding and extraction. Certain operations that can be performed using a regular expression can also be accomplished using methods of the String class. For example, to find whether a...