正则语法努力学习中
一：使用NSPredicate(谓词)匹配
NSString *mail = @"zhangrongwuios@icloud.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:mail];
二：rangeOfString: option: 进行搜索
NSString *text = @"// Do any additional setup after loading the view, typically from a nib.";
NSRange range = [text rangeOfString:@"(?:[^,])*\\." options:NSRegularExpressionSearch];
if (range.location != NSNotFound) {
NSLog(@"%@", [text substringWithRange:range]);
}
三：使用iOS系统正则表达类
NSString *text = @"// Do any additional setup after loading the typically from a nib. view, typically from a nib.";
NSError *error = NULL;
NSRegularExpression *regx = [NSRegularExpression regularExpressionWithPattern:@"(?:[^,])*\\." options:NSRegularExpressionCaseInsensitive error:&error];
// 匹配多个
NSArray<NSTextCheckingResult *> *results = [regx matchesInString:text options:0 range:NSMakeRange(0, text.length)];
[results enumerateObjectsUsingBlock:^(NSTextCheckingResult * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"%@", obj);
if (obj) {
NSLog(@"多次匹配结果 ：%@", [text substringWithRange:obj.range]);
}
}];
// 匹配单个
NSTextCheckingResult *result = [regx firstMatchInString:text options:0 range:NSMakeRange(0, [text length])];
if (result) {
NSLog(@"%@", [text substringWithRange:result.range]);
}
