我正在使用C#和MVC3。
我有一个页面,例如学生列表,它显示了由数据库驱动的学生列表。同时我的菜单是数据库驱动的,所以我也必须将它发送到视图。
如何将两个模型发送到单个视图?
答案 0 :(得分:14)
您应始终为视图创建单独的ViewModel。您的视图应该从您的域模型中抽象出来。在演示/教程中,他们通过简单地强烈键入视图到域模型来显示它非常简单,但这不是一个好策略。视图不应该依赖于业务对象。
即使需要将域模型映射到另一个视图模型类,您也应该为当前场景以及所有其他视图实现David Glenn的建议解决方案。
修改强>
如果你有一个顶级菜单> TopMenu.aspx
你在里面有多个局部视图> StudentMenu.ascx
,ResultMenu.ascx
您将为顶层菜单创建一个视图模型> TopMenuViewModel.cs
您还将为部分视图创建视图模型> StudentMenuViewModel
,ResultMenuViewModel
等。
并且您的TopMenuViewModel将同时具有>
class TopMenuViewModel
{
//all the stuff required in TopMenu.aspx
StudentMenuViewModel studentvm;
ResultMenuViewModel resultvm;
}
并在TopMenu.aspx
渲染部分时,您将传递相关的视图模型>
Html.RenderPartial('StudentView', Model.studentvm)
希望它有意义
答案 1 :(得分:10)
您可以创建一个ViewModel,它代表您的视图,而不是您的商业模式
public class StudentPage {
public IEnumerable<Student> Students { get; set; }
public Menu Menu { get; set; }
}
然后您的控制器将ViewModel返回到您的视图
public ViewResult Students() {
var menu = GetMenu();
var students = Repository.Students();
var model = new StudentPage {
Menu = menu,
Students = students
}
return View(model);
}
我假设菜单是您网页上的一个重复出现的功能,所以您可能想要将其分解为
public class BasePage {
public Menu Menu { get; set; }
}
public class StudentPage : BasePage {
public IEnumerable<Student> Students { get; set; }
}
您还可以创建一个具有GetMenu()
功能的基本控制器,以便在多个控制器之间重复使用。
答案 2 :(得分:3)
注意:下面的类应该在.net 3.5及更低版本中使用,因为.net 4是作为类似的类
Tuple
引入的,应该替代使用。
MultiObject<O1, O2, ..>
和MultiList<L1, L2, ...>
这就是我编写这样的控制器动作和视图的方法:
public ActionResult MultiModel()
{
MultiList<User, Company> result = MultiList.New(
this.repository.GetUsers(),
this.repository.GetCompanies()
);
return View(result);
}
我的观点是:
ViewPage<MultiList<User, Company>>
我正在使用这个可重复使用的便利类:
#region MultiObject static helper class
/// <summary>
/// Provides static methods for creating multi objects with type inference.
/// </summary>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
public static class MultiObject
{
/// <summary>
/// Creates a new <see cref="MultiObject{T1, T2}"/> object instance.
/// </summary>
/// <typeparam name="T1">The type of the first object.</typeparam>
/// <typeparam name="T2">The type of the second object.</typeparam>
/// <param name="first"><typeparamref name="T1"/> object instance.</param>
/// <param name="second"><typeparamref name="T2"/> object instance.</param>
/// <returns>
/// Returns a <see cref="MultiObject{T1, T2}"/> of <typeparamref name="T1"/> and <typeparamref name="T2"/> object instances.
/// </returns>
public static MultiObject<T1, T2> New<T1, T2>(T1 first, T2 second)
{
return new MultiObject<T1, T2>(first, second);
}
/// <summary>
/// Creates a new <see cref="MultiObject{T1, T2, T3}"/> object instance.
/// </summary>
/// <typeparam name="T1">The type of the first object.</typeparam>
/// <typeparam name="T2">The type of the second object.</typeparam>
/// <typeparam name="T3">The type of the third object.</typeparam>
/// <param name="first"><typeparamref name="T1"/> object instance.</param>
/// <param name="second"><typeparamref name="T2"/> object instance.</param>
/// <param name="third"><typeparamref name="T3"/> object instance.</param>
/// <returns>
/// Returns a <see cref="MultiObject{T1, T2, T3}"/> of <typeparamref name="T1"/>, <typeparamref name="T2"/> and <typeparamref name="T3"/> objects instances.
/// </returns>
public static MultiObject<T1, T2, T3> New<T1, T2, T3>(T1 first, T2 second, T3 third)
{
return new MultiObject<T1, T2, T3>(first, second, third);
}
}
#endregion
#region MultiObject<T1, T2>
/// <summary>
/// Represents a 2-multi object, or pair.
/// </summary>
/// <typeparam name="T1">The type of the multi object's first component.</typeparam>
/// <typeparam name="T2">The type of the multi object's second component.</typeparam>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
public class MultiObject<T1, T2>
{
/// <summary>
/// Gets or sets the value of the first multi object component.
/// </summary>
/// <value>The first.</value>
public T1 First { get; set; }
/// <summary>
/// Gets or sets the value of the second multi object component.
/// </summary>
/// <value>The second multi object component value.</value>
public T2 Second { get; set; }
/// <summary>
/// Initializes a new instance of the <see cref="MultiObject{T1, T2}"/> class.
/// </summary>
/// <param name="first">Multi object's first component value.</param>
/// <param name="second">Multi object's second component value.</param>
public MultiObject(T1 first, T2 second)
{
this.First = first;
this.Second = second;
}
}
#endregion
#region MultiObject<T1, T2, T3>
/// <summary>
/// Creates a new 3-multi object, or triple.
/// </summary>
/// <typeparam name="T1">The value of the first component of the multi object.</typeparam>
/// <typeparam name="T2">The value of the second component of the multi object.</typeparam>
/// <typeparam name="T3">The value of the third component of the multi object.</typeparam>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
[SuppressMessage("Microsoft.Design", "CA1005:AvoidExcessiveParametersOnGenericTypes")]
public class MultiObject<T1, T2, T3> : MultiObject<T1, T2>
{
/// <summary>
/// Gets or sets the value of the third multi object component.
/// </summary>
/// <value>The third multi object component value.</value>
public T3 Third { get; set; }
/// <summary>
/// Initializes a new instance of the <see cref="MultiObject{T1, T2, T3}"/> class.
/// </summary>
/// <param name="first">Multi object's first component value.</param>
/// <param name="second">Multi object's second component value.</param>
/// <param name="third">Multi object's third component value.</param>
public MultiObject(T1 first, T2 second, T3 third)
: base(first, second)
{
this.Third = third;
}
}
#endregion
当我必须传递多个列表时
#region MultiObject static helper class
/// <summary>
/// Provides static methods for creating multi objects with type inference.
/// </summary>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
public static class MultiList
{
/// <summary>
/// Creates a new <see cref="MultiObject{T1, T2}"/> object instance.
/// </summary>
/// <typeparam name="T1">The type of the first object.</typeparam>
/// <typeparam name="T2">The type of the second object.</typeparam>
/// <param name="first"><typeparamref name="T1"/> object instance.</param>
/// <param name="second"><typeparamref name="T2"/> object instance.</param>
/// <returns>
/// Returns a <see cref="MultiObject{T1, T2}"/> of <typeparamref name="T1"/> and <typeparamref name="T2"/> object instances.
/// </returns>
public static MultiList<T1, T2> New<T1, T2>(IList<T1> first, IList<T2> second)
{
return new MultiList<T1, T2>(first, second);
}
/// <summary>
/// Creates a new <see cref="MultiObject{T1, T2, T3}"/> object instance.
/// </summary>
/// <typeparam name="T1">The type of the first object.</typeparam>
/// <typeparam name="T2">The type of the second object.</typeparam>
/// <typeparam name="T3">The type of the third object.</typeparam>
/// <param name="first"><typeparamref name="T1"/> object instance.</param>
/// <param name="second"><typeparamref name="T2"/> object instance.</param>
/// <param name="third"><typeparamref name="T3"/> object instance.</param>
/// <returns>
/// Returns a <see cref="MultiObject{T1, T2, T3}"/> of <typeparamref name="T1"/>, <typeparamref name="T2"/> and <typeparamref name="T3"/> objects instances.
/// </returns>
public static MultiList<T1, T2, T3> New<T1, T2, T3>(IList<T1> first, IList<T2> second, IList<T3> third)
{
return new MultiList<T1, T2, T3>(first, second, third);
}
}
#endregion
#region MultiList<T1, T2>
/// <summary>
/// Represents a 2-multi object, or pair.
/// </summary>
/// <typeparam name="T1">The type of the multi object's first component.</typeparam>
/// <typeparam name="T2">The type of the multi object's second component.</typeparam>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
public class MultiList<T1, T2> : MultiObject<IList<T1>, IList<T2>>
{
/// <summary>
/// Initializes a new instance of the <see cref="MultiList<T1, T2>"/> class.
/// </summary>
/// <param name="first">The first.</param>
/// <param name="second">The second.</param>
public MultiList(IList<T1> first, IList<T2> second) : base(first, second) { }
}
#endregion
#region MultiList<T1, T2, T3>
/// <summary>
/// Creates a new 3-multi object, or triple.
/// </summary>
/// <typeparam name="T1">The value of the first component of the multi object.</typeparam>
/// <typeparam name="T2">The value of the second component of the multi object.</typeparam>
/// <typeparam name="T3">The value of the third component of the multi object.</typeparam>
[SuppressMessage("Microsoft.Naming", "CA1704:IdentifiersShouldBeSpelledCorrectly", MessageId = "Multi")]
[SuppressMessage("Microsoft.Design", "CA1005:AvoidExcessiveParametersOnGenericTypes")]
public class MultiList<T1, T2, T3> : MultiObject<IList<T1>, IList<T2>, IList<T3>>
{
/// <summary>
/// Initializes a new instance of the <see cref="MultiList<T1, T2, T3>"/> class.
/// </summary>
/// <param name="first">The first.</param>
/// <param name="second">The second.</param>
/// <param name="third">The third.</param>
public MultiList(IList<T1> first, IList<T2> second, IList<T3> third) : base(first, second, third) { }
}
#endregion
但是在您要传递菜单的情况下,最好有一个基页类,所有页面都继承自该页面类,并且该页面类提供所有常用属性(菜单数据为一个)。
答案 3 :(得分:2)
要在单个视图中处理多个模型,我个人使用ViewBag。
请注意,如果您使用ViewBag,您将从编译器获得的所有帮助都被禁用,并且运行时错误/错误发生的可能性比属性已经在“普通”对象上的情况更多,并且编译器会捕获错别字。
这是使用动态对象的缺点,但是,还有许多其他优点。在您的控制器中,您只需将数据/模型传递到ViewBag:
public ActionResult Index() {
ViewBag.TopMenu = TopMenu();
ViewBag.Student = Student();
return View();
}
然后在视图中,将其调出:
@{
ViewBag.Title = "Index_ViewBag";
}
<h2>Index View Bag</h2>
<table>
<tr>
@foreach (var menu in ViewBag.TopMenu)
{
<td>
<a href="@menu.URL">@menu.Name</a>
</td>
}
</tr>
</table>
<p>
<ul>
@foreach (var student in ViewBag.Student)
{
<li>
<a href="@student.URL">@student.Name</a>
</li>
}
</ul>
</p>
答案 4 :(得分:0)
还有另一种选择,由一些MVC纯粹主义者提出,但我发现它对我有用。您可以在学生视图中显示菜单,而不是在每个页面上都包含两个模型(我假设几乎所有页面都是这样):
@Html.RenderAction("Menu");
将调用它自己的操作,生成菜单视图模型和“菜单”。部分观点。
对我而言,这是有道理的,但我知道很多人不喜欢它。
答案 5 :(得分:0)
在.Net Framework 4.0中,您可以使用动态模型。
大致是:
public class HomeController : Controller
{
public ActionResult Index()
{
dynamic viewmodel = new ExpandoObject();
viewmodel.Students = MyStudent();
viewmodel.MenuItems = MyMenuItems();
return View(mymodel);
}
}
如何在视图代码中访问:
@model dynamic
@foreach (Student student in Model.Students)
}
<h1>@student.Name</h1>
}
@foreach (MenuItem menuItem in Model.MenuItems)
{
<h1>@menuItem.menuname</h1>
}