iOS 常用正则表达式整理

1、设置4-14位的英文和数字输入

    NSString *regex = @"^[A-Za-z0-9]{4,14}$";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
    BOOL isMatch = [pred evaluateWithObject:text];

2、判断是否全数字，非正则

　　 NSScanner* scan = [NSScanner scannerWithString:str];
    int val;
    return [scan scanInt:&val] && [scan isAtEnd];

3、判断是否是邮箱格式

　　　　NSString *regex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}"; 
       NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
       BOOL result = [emailTest evaluateWithObject:email];