asp.net-mvc – 部分视图模型无法解析

public class ModelA
{
    public bool Prop1 {get;set;}
    public bool Prop2 {get; set;}
    public Dictionary<int,string> Prop3{get; set;}
    public int Prop4 {get; set;}
    public ModelB Prop5 { get; set; }


    public ModelA ()
    {
        Prop5 = null;

       ... more code ...
    }
}

//This view is tied to ModelA
@using (Html.BeginForm("CreateReport","Home",FormMethod.Post))
{
   some markup
}

//this is the problem
@Html.Partial("FileLinks",Model.Prop5) //This line throws an error

Error: The model item passed into the dictionary is of type ‘ModelA’,but this dictionary requires a model item of type ‘ModelB’

如果我将其更改为@ Html.Partial(“FileLinks”,new ModelB()),该行可以工作

为什么原始代码不起作用？该属性为ModelB类型.

任何帮助表示赞赏谢谢！

更新：我忘了从Controller添加一些代码

m.FileLinks = new ModelB()
返回视图(“索引”,m)

所以模型不是空的