1.利用NSPRedicate(谓词)匹配例如匹配有效邮箱:NSString *email = @“nijino_saki@163.com”; NSString *regex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+//.[A-Za-z]{2,4}"; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex]; BOOL isValid = [predicate evaluateWithObject:email];谓词匹配比较灵活,但是需要有谓词的相关知识。2.利用rangeOfString:option:直接查找 NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib."; NSRange range = [searchText rangeOfString:@"(?:[^,])*//." options:NSRegularExpressionSearch]; if (range.location != NSNotFound) { NSLog(@"%@", [searchText substringWithRange:range]); }options中设定NSRegularExpressionSearch就是表示利用正则表达式匹配,会返回第一个匹配结果的位置。3.使用正则表达式类 NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib."; NSError *error = NULL; NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?:[^,])*//." options:NSRegularExpressionCaseInsensitive error:&error]; NSTextCheckingResult *result = [regex firstMatchInString:searchText options:0 range:NSMakeRange(0, [searchText length])]; if (result) { NSLog(@"%@/n", [searchText substringWithRange:result.range]); }使用系统的正则表达式类(NSRegularExpression)会返回匹配的多个结果。小结:第一种匹配需要学习NSPredicate的写法,需要查阅苹果相关技术文档;如果只关心第一个匹配的结果,第二种匹配较为简洁;如果需要匹配多个结果,同时匹配多次,第三种方式效率会更高。
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