建立MVC CMS

假设您使用的是ASP.NET MVC,并且您希望保持它的简单性,那么下面的内容如何:

public abstract class TemplateBase
{
    public abstract string TemplateName { get; }
}

public class SingleColumnTemplate : TemplateBase
{
    public override string TemplateName { get { return "Single-column page"; } }
    public AreaContainer CenterColumn { get; protected set; }

    public SingleColumnTemplate()
    {
        CenterColumn = new AreaContainer("Center column");
    }
}

public class TwoColumnTemplate : TemplateBase
{
    public override string TemplateName { get { return "Two-column page"; } }
    public AreaContainer LeftColumn { get; protected set; }
    public AreaContainer RightColumn { get; protected set; }

    public TwoColumnTemplate()
    {
        LeftColumn = new AreaContainer("Left column");
        RightColumn = new AreaContainer("Right column");
    }
}

// TODO Add more template types

public class AreaContainer
{
    public string ContainerName { get; set; }
    public IList<AreaBase> Areas { get; protected set; }

    public AreaContainer(string name)
    {
        ContainerName = name;
        Areas = new List<AreaBase>();
    }
}

public abstract class AreaBase
{
    public abstract string AreaName { get; }
}

public class HtmlArea : AreaBase
{
    public override string AreaName { get { return "HTML content"; } }
    public string HtmlContent { get; set; }
}

// TODO Add more area types

public class Page
{
    public int Id { get; set; }
    public string Title { get; set; }
    public TemplateBase Template { get; set; }
}

编辑现有页面的控制器操作可能看起来像:

public class PageAdminController : Controller
{
    [HttpGet]
    ActionResult Edit(int id) 
    {
        var page = GetPageFromStorageById(id);
        // TODO If the page is not found, issue 404
        return View(page);
    }

    // ...
}

在视野中( Views/PageAdmin/Edit.aspx ),它应该强类型为 ViewPage<Page> ,您可以使用 HtmlHelper.EditorFor(...) 方法以呈现适当的模板视图,前提是已为每个模板类型创建了部分视图:

<!-- Inside the edit view for Page (Edit.aspx) -->
<%: Html.HiddenFor(m => m.Id) %>
<%: Html.EditorFor(m => m.Title) %>
<%: Html.EditorFor(m => m.Template) %>

在文件夹中 Views/PageAdmin/EditorTemplates SingleColumnTemplate.ascx , TwoColumnTemplate.ascx HtmlArea.ascx ). 您可能还希望为 AreaContainer .

Page 具有类型的属性 TemplateBase ,这是一个抽象类 DefaultModelBinder 不知道如何填充它。您可以通过编写自定义模型绑定器来解决这个问题,该绑定器不知何故“知道”要实例化哪个实现类。它怎么会知道呢?我可以想到的一个选项是在视图中包含一个隐藏字段,该字段包含页面模板的实际运行时类型的名称。我想这有点老生常谈,但既然你追求简单,我想没问题。在这种情况下,只需包含一个名为的属性, RuntimeTypeName 模板库 班级:

public string RuntimeTypeName { get { return GetType().FullName; } }

因为它只是打电话 GetType()

然后必须确保为 模板库 TemplateBase.RuntimeTypeName 财产。换句话说,在 单列模板.ascx 和 两列模板.ascx

<%: Html.HiddenFor(m => m.RuntimeTypeName) %>

使用此信息创建正确类型模板的模型活页夹可能如下所示:

/// <summary>
/// Model binder hack that builds upon the DefaultModelBinder, 
/// but that can detect the "proper" subclass/implementing class 
/// type for a model, assuming the name of that type is contained
/// in a field called "RuntimeTypeName".
/// </summary>
public class InheritanceSupportingModelBinder : DefaultModelBinder
{
    // Assume that the name of the field that contains the 
    // runtime type name is called "RuntimeTypeName"
    public const string RuntimeTypeNameField = "RuntimeTypeName";
    private Type RuntimeType { get; set; }

    // This method is called by the DefaultModelBinder to find out which
    // properties of the current model that it should attempt to bind
    protected override PropertyDescriptorCollection GetModelProperties(
        ControllerContext controllerContext, ModelBindingContext bindingContext)
    {
        // If we have found out the runtime type of the model through
        // looking at the "special" field above, use the properties of that type.
        // Otherwise, use the default behavior.
        if (RuntimeType != null)
        {
            return TypeDescriptor.GetProperties(RuntimeType);
        }
        else
        {
            return base.GetModelProperties(controllerContext, bindingContext);
        }
    }

    // This method is called by the DefaultModelBinder when it 
    // tries to create an instance of the model class. If the 
    // class is abstract, an exception will be thrown. Therefore
    // we try to read the name of the actual type from the 
    // RuntimeTypeName (hidden) field and return an instance of that type.
    protected override object CreateModel(ControllerContext controllerContext, 
                                          ModelBindingContext bindingContext, 
                                          Type modelType)
    {
        if (bindingContext.ValueProvider.ContainsPrefix(
            bindingContext.ModelName + "." + RuntimeTypeNameField))
        {
            var result = bindingContext.ValueProvider.GetValue(
                bindingContext.ModelName + "." + RuntimeTypeNameField);

            if (result != null && !string.IsNullOrEmpty(result.AttemptedValue))
            {
                // Check that the type indicated by the hidden field is really
                // a subclass of (or implementing) the indicated base class
                var tempType = Type.GetType(result.AttemptedValue);
                if (modelType.IsAssignableFrom(tempType))
                {
                    RuntimeType = modelType = tempType;
                }
            }
        }
        return base.CreateModel(controllerContext, bindingContext, modelType);
    }
}

免责声明: 我自己也是ASP.NET MVC的初学者,所以这个模型活页夹很可能有问题。我通过查看 通过反复试验。这只是一个例子,但根据我(快速和肮脏)的测试,它似乎是可行的。

当然,您需要在Global.asax中注册它才能启动:

ModelBinders.Binders.Add(
    typeof(TemplateBase), 
    new InheritanceSupportingModelBinder());

但我们还没结束!记住 AreaContainer.Areas IList<AreaBase> -从那以后 AreaBase 也是一个抽象类,我们必须应用相同的技巧才能正确绑定它。也就是说,添加 财产 面积基准 面积基准 Global.asax .

如果我们已经遵循了所有这些步骤,我们可以在 PageAdminController

[HttpPost]
public ActionResult Edit(Page page)
{
    if (!ModelState.IsValid)
    {
        return View(page);
    }
    // TODO Save page to database or whatever
    // TODO Redirect to page index
}

创建一个新页面的操作方法只是一个练习,应该没那么难(用户从列表中选择模板,显示正确的表单,像上面这样的后期处理操作)。

HtmlHelper.DisplayFor(...) 而不是 EditorFor(...) ,创建相应的局部视图,然后设置。

对于所见即所得的内容编辑,您可能希望使用第三方组件。 CKEditor TinyMCE , YUI Rich Text Editor 和 Telerik Editor 是一些例子。