iOS搜索指定字符在字符串中的位置

 NSString *tmpStr = @"asd341234aaaaccd";  

   NSRange range;  

   range = [tmpStr rangeOfString:@"ccd"];  

 if (range.location != NSNotFound) {  

       NSLog(@"found at location = %lu, length = %lu",(unsigned long)range.location,(unsigned long)range.length);  

 NSString *ok = [tmpStr substringFromIndex:range.location];  

       NSLog(@"%@",ok);  

   }else{  

       NSLog(@"Not Found");  

   }