常用正则表达式

1、匹配两个字符串之间的内容

NSString *startStr = @"aaaa";

NSString *endStr = @"bbb";

NSString *str = @"aaaa8888999bbbkdkdkdkd";

NSString *regex = [NSString stringByFormat:@"%@[sS]*?%@",startStr,endStr];   //正则规则