编辑（用于更新的帖子）：

有没有一种方法可以通过将名称与类型哈希在一起来获取类型？

这样的事情是你要去的吗？dotnetfiddle链接

public interface IProperty
{
    object Value { get; }
    Type TypeOfValue { get; }
}

public class Property : IProperty
{
    public object Value { get; set; }
    public Type TypeOfValue { get; set; }
    public override string ToString() { return TypeOfValue.FullName + ": " + Value; }
}

public class Observable
{
    public readonly Dictionary<string, Property> 
        Properties = new Dictionary<string, Property>();

    // use interface so consumer of your property can't mess with the
    // type or value stored in your dictionary within Observable
    public IProperty Get(string name)
    {
        Property obj;
        if (Properties.TryGetValue(name, out obj)){
            return obj;
        }

        // throw something which makes more sense to you
        throw new ArgumentException(name + " does not exist in the dictionary");
    }

    // sample of how you'd store these properties
    public void Set(string name, object val)
    {
        if (Properties.ContainsKey(name)){
            Properties[name].Value = val;
            Properties[name].TypeOfValue = val.GetType();
        } else {
            Properties[name] = new Property {
                Value = val,
                TypeOfValue = val.GetType()
            };
        }
    }
}

原始答案：

您可能无意中将而不是插入astring到字典中，如果是这样，问题就出在您发布的代码中，而不是在您要插入而不是的地方。ObservableProperty<string>stringProperty<string>

如果您不喜欢无效的强制转换异常，则有两种解决方案。

解决方案1：自定义函数引发的错误。

如果您想保留Get<T>(...)I的签名，建议您进行一些错误处理。您看到的错误是因为字典中的属性属于类型string，而不是类型Property<string>。以下代码将为您提供一些可用于更多错误处理的东西。

public class Observable
{
    public readonly Dictionary<string, object> 
        Properties = new Dictionary<string, object>();

    public Property<T> Get<T>(string name)
    {
        object obj;
        if (Properties.TryGetValue(name, out obj)){
            try {
                return (Property<T>) obj;
            } catch(InvalidCastException){
                // throw something which makes more sense to you
                throw new ArgumentException("Could not cast the given object to the desired type");
            }
        }

        // throw something which makes more sense to you
        throw new ArgumentException(name + " does not exist in the dictionary");
    }
}

解决方案2：返回一般 object

public class Observable
{
    public readonly Dictionary<string, object> 
        Properties = new Dictionary<string, object>();

    public object Get(string name)
    {
        object obj;
        if (Properties.TryGetValue(name, out obj)){
            return obj;
        }

        // or do whatever you want when the given key doesn't exist.
        return null;
    }
}