在断开循环时检测

Question

任何人都可以请求帮助,因为我在这里遇到了一堵墙,我怎么能检测到我因为无效值而突然出现循环.

例如,如果有人为孩子输入年龄为3 5 6 7 9就可以了,如果输入o 3 5 6 7,这将在我的代码中返回-1并退出循环.

我如何检测并返回消息

public static int IntIsValid(string p)
        {
            int pn;
            bool isNum = int.TryParse(p, out pn);
            int pnIsvalid = isNum ? pn : -1;
            return pnIsvalid;
        }

string addDash  = Regex.Replace(agesOfChildren, " ", "_");
            string[] splitNumberOfChildren  = addDash.Split('_');
            string splitChildrensAge        = string.Empty;
            int checkAgeOfChildren          = 0;
            string problem = string.Empty;
            foreach (var splitAgeOfChild in splitNumberOfChildren)
            {
                splitChildrensAge           = splitAgeOfChild;
                checkAgeOfChildren          = RemoveInvalidInput.IntIsValid(splitChildrensAge);
                if (checkAgeOfChildren == -1)
                {
                    problem = "problem with age, stop checking";
                    break;
                }
            }

所以我想做像这样的事情

if(error with loop == true)
{
ViewBag.Message = problem;
}

希望有人可以提供帮助,因为我已经空白了

乔治

Answer 1

很简单,你已经给出了答案:

boolean error_with_loop = false;
foreach (var splitAgeOfChild in splitNumberOfChildren) {
      splitChildrensAge           = splitAgeOfChild;
      checkAgeOfChildren          = RemoveInvalidInput.IntIsValid(splitChildrensAge);
      if (checkAgeOfChildren == -1)
      {
           error_with_loop = true;
           problem = "problem with age, stop checking";
           break;
      }
}

if (error_with_loop) {
    ViewBag.Message = problem;
}

或者你抛出一个Exception:

try {
    foreach (var splitAgeOfChild in splitNumberOfChildren) {
          splitChildrensAge           = splitAgeOfChild;
          checkAgeOfChildren          = RemoveInvalidInput.IntIsValid(splitChildrensAge);
          if (checkAgeOfChildren == -1)
          {
                // note: no need to break
                throw new ErrorWithLoopException();
          }
    }
} catch (ErrorWithLoopException e) {
    ViewBag.Message = problem;
}

实际上,您似乎使用某种整数验证.这个Int32类有例外:http://msdn.microsoft.com/en-us/library/system.int32.parse%28v=vs.71%29.aspx你的代码实际上会更短(不知道如果它适用,因为我不知道你的验证代码做了什么额外的):

try {
    foreach (var splitAgeOfChild in splitNumberOfChildren) {
          splitChildrensAge           = splitAgeOfChild;
          checkAgeOfChildren          = Int32.Parse(splitChildrensAge);
    }
} catch (FormatException e) {
    ViewBag.Message = problem;
}