C# 列表计数与数据验证

Question

感谢您的反馈。我仍然遇到超出范围的异常。我正在调试，但不明白为什么会出现异常。如果一个 int 高于某个其他 int，它应该可以工作。跟length.Count有关系吗？

更新代码

                    do
                {
                    Console.Write("Input the element that you want to exclude from the list: ");
                    result = int.TryParse(Console.ReadLine(), out delSelection);

                    tempInputDelInt = (int)(tempList[delSelection]);
                    tempInputDelStr = Convert.ToString(tempInputDelInt);

                    if (result == true && tempInputDelInt >= 0 && tempInputDelInt < tempList.Count)
                    {
                        tempList.RemoveAt(delSelection);
                        Console.WriteLine("\nYou've deleted the temperature " + tempInputDelStr + " from index " + delSelection);
                        success = false;
                        Console.ReadKey(true);
                        Console.Clear();
                    }

                    else if (result == true && tempInputDelInt >= tempList.Count || tempInputDelInt < 0)
                    {
                        Console.WriteLine("You've input a number that's outside the list. Input a digit between 0 and " + (tempList.Count - 1) + ".\n");
                        success = true;
                        Console.ReadKey(true);
                    }

                    else if (result == false)
                    {
                        Console.WriteLine("\nYou didn't input a digit, try again!\n");
                        success = true;
                        Console.ReadKey(true);
                    }
                } while (success);
                success = false;

我在验证第一个 else if 语句时遇到一些问题。我想捕捉输入数组外的值的情况，但我没能做到。

我用 array.Length 成功地完成了一个几乎相同的程序。

array.List和list.Count有区别吗？那是问题所在吗？

在此先感谢您的帮助！

                    do
                {
                    Console.Write("Input the element that you want to exclude from the list: ");
                    result = int.TryParse(Console.ReadLine(), out delSelection);


                    tempInputDel = Convert.ToString(tempList[delSelection]);

                    if (result == true && delSelection >= 0 && delSelection < tempList.Count)
                    {
                        tempList.RemoveAt(delSelection);
                        Console.WriteLine("\nYou've deleted the temperature " + tempInputDel + " from index " + delSelection);
                        Console.ReadKey(true);
                        Console.Clear();
                    }

                    else if (result == true && delSelection >= tempList.Count || delSelection < 0)
                    {
                        Console.WriteLine("You've input a number that's outside the list. Input a digit between 0 and " + (tempList.Count - 1) + ".\n");

                    }

                    else if (result == false)
                    {
                        Console.WriteLine("\nYou didn't input a digit, try again!");
                        Console.ReadKey(true);
                    }
                } while (result == false);

Answer 1

我假设您的超出范围异常发生在这里：

tempInputDel = Convert.ToString(tempList[delSelection]);

如果 delSelection 在 tempList 的范围内，则不能在检查之前执行此操作。将它移到第一个 if 块内。

一般建议：

您可以使用调试器逐步从一条语句转到另一条语句，以找到（例如）抛出异常的确切源代码位置。

Answer 2

改变这个

tempInputDelInt = (int)(tempList[delSelection]);

至此

tempInputDelInt = (int)delSelection;

无论用户输入什么数字，您都在使用它作为索引来确定要删除的项目。所以这不是您从 tempList 获得的值。

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