ASP.NET MVC5实体框架组字段(国家，州)的帐户

我有公司、国家和州三个类。州与国家有关州和国家是公司的外部关键

问题公司视图将州和国家显示为单独的下拉列表。但是我希望当我选择State时，相应的Country应该改变，反之亦然。这在MVC5 EF模型中可能吗?

public class Company
{
    public int CompanyID { get; set; }
    [Required]
    [StringLength(100,MinimumLength=3)]
    public string Name { get; set; }
    [StringLength(200)]
    public string Address { get; set; }
    public int? StateID { get; set; }
    public virtual State State { get; set; }
    public int? CountryID { get; set;}
    public virtual Country Country { get; set; }
    public int CompanyTypeID { get; set; }
    public virtual CompanyType CompanyType { get; set; }
}

国家类

public class Country
{
    public int CountryID { get; set; }
    [Required]
    [StringLength(100)]
    public string Name { get; set; }
    public virtual ICollection<State> States { get; set; }
    public virtual ICollection<Company> Companies { get; set; }
}

状态类

public class State
{
    public int StateID { get; set; }
    [Required]
    [StringLength(100)]
    public string Name { get; set; }
    public int CountryID { get; set; }
    public virtual Country Country { get; set; }
    public virtual ICollection<Company> Companies { get; set; }
}

我已经搭建并生成了视图和Company视图以供参考

@using (Html.BeginForm()) {
@Html.AntiForgeryToken()
<div class="form-horizontal">
    <h4>Company</h4>
    <hr />
    @Html.ValidationSummary(true, "", new { @class = "text-danger" })
    <div class="form-group">
        @Html.LabelFor(model => model.Name, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.Name, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.Name, "", new { @class = "text-danger" })
        </div>
    </div>
    <div class="form-group">
        @Html.LabelFor(model => model.Address, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.Address, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.Address, "", new { @class = "text-danger" })
        </div>
    </div>
    <div class="form-group">
        @Html.LabelFor(model => model.StateID, "StateID", htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.DropDownList("StateID", null, htmlAttributes: new { @class = "form-control" })
            @Html.ValidationMessageFor(model => model.StateID, "", new { @class = "text-danger" })
        </div>
    </div>
    <div class="form-group">
        @Html.LabelFor(model => model.CountryID, "CountryID", htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.DropDownList("CountryID", null, htmlAttributes: new { @class = "form-control" })
            @Html.ValidationMessageFor(model => model.CountryID, "", new { @class = "text-danger" })
        </div>
    </div>
    <div class="form-group">
        @Html.LabelFor(model => model.CompanyTypeID, "CompanyTypeID", htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.DropDownList("CompanyTypeID", null, htmlAttributes: new { @class = "form-control" })
            @Html.ValidationMessageFor(model => model.CompanyTypeID, "", new { @class = "text-danger" })
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-offset-2 col-md-10">
            <input type="submit" value="Create" class="btn btn-default" />
        </div>
    </div>
</div> } <div> @Html.ActionLink("Back to List", "Index")

@section Scripts {@Scripts.Render("~/bundles/jqueryval")}

如有任何帮助，不胜感激