c# - Dictionary<>.ContainsKey 给出 RuntimeBinderException

Question

在 .cshtml 中，我想检查 a 中是否存在密钥，Directory<int, Object>但总是出错并且找不到原因。

这是我的代码：

@foreach (KeyValuePair<int, int> weekAndYear in @ViewBag.WeekAndYears)
{
    int key = int.Parse(weekAndYear.Value + "" + weekAndYear.Key);

    bool exist = ViewBag.Menus.ContainsKey(key);
}

我得到的错误：

The best overloaded method match for System.Collections.Generic.Dictionary<int,Object>.this[int] has some invalid arguments

当我只使用 .Key 或 .Value 时，它​​仍然有效。

编辑 - 解决方案

问题是什么，我不知道，但我已经用下面的代码解决了这个问题：

foreach (KeyValuePair<int, int> weekAndYear in @ViewBag.WeekAndYears)
    {
        int key = int.Parse(weekAndYear.Value + "" + weekAndYear.Key);

        bool exist = ((Dictionary<int, Object>)ViewBag.Menus).ContainsKey(key);
}

Answer 1

您是否可以尝试使用 TryGetValue 而不是 ContainsKey 并查看它是否有效：

@foreach (KeyValuePair<int, int> weekAndYear in @ViewBag.WeekAndYears)
{
    int key = int.Parse(weekAndYear.Value + "" + weekAndYear.Key); 
    Object outValue;
    bool exist = Menus.TryGetValue(key, out outValue);
}

Answer 2

问题是什么，我不知道，但我已经用下面的代码解决了这个问题：

foreach (KeyValuePair<int, int> weekAndYear in @ViewBag.WeekAndYears)
    {
        int key = int.Parse(weekAndYear.Value + "" + weekAndYear.Key);

        bool exist = ((Dictionary<int, Object>)ViewBag.Menus).ContainsKey(key);
}