How do I pass value to MVC3 master page ( _layout)?

问题

I have a custom modelbinder, its check the authentication cookie and return the value.

public class UserDataModelBinder<T> : IModelBinder
{
    public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
    {

        if (controllerContext.RequestContext.HttpContext.Request.IsAuthenticated)
        {
            var cookie =
                controllerContext.RequestContext.HttpContext.Request.Cookies[FormsAuthentication.FormsCookieName];

            if (cookie == null)
                return null;

            var decrypted = FormsAuthentication.Decrypt(cookie.Value);

            if (!string.IsNullOrWhiteSpace(decrypted.UserData))
                return JsonSerializer.DeserializeFromString<T>(decrypted.UserData);
        }

        return null;
    }
}

if I need to use it, I just need to pass it to the action. everything works.

public ActionResult Index(UserData userData)
{
    AccountLoginWidgetVM model = new AccountLoginWidgetVM();
    if (null != userData)
        model.UserData = userData;

    return View(userData);
}

However, I want to use it in my master page, because once user login, i want to display their info on the top on every page. I tried a few things, coudln't get it work

 @Html.RenderPartial("LoginPartial", ???model here??)

回答1:

We did it as follows:

Defined separate viewmodel for masterpages.

public class MasterPageViewModel
{
    public Guid CurrentUserId { get; set; }
    public string CurrentUserFullName { get; set; }
}

Added injection filter and filter provider.

public class MasterPageViewModelInjectorFilterProvider: IFilterProvider
{
    public IEnumerable<Filter> GetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
    {
        return new [] {new Filter(new MasterPageViewModelInjectorFilter(), FilterScope.Action, null), };
    }

    private class MasterPageViewModelInjectorFilter: IResultFilter
    {
        public void OnResultExecuting(ResultExecutingContext filterContext)
        {
            var viewResult = filterContext.Result as ViewResult;
            if (viewResult == null)
                return;

            if (viewResult.ViewBag.MasterPageViewModel != null)
                return;

            //setup model whichever way you want
            var viewModel = new MasterPageViewModel();
            //inject model into ViewBag
            viewResult.ViewBag.MasterPageViewModel = viewModel;
        }

        public void OnResultExecuted(ResultExecutedContext filterContext)
        {
        }
    }
}

Configure filter provider:

//in Application_Start
FilterProviders.Providers.Add(new MasterPageViewModelInjectorFilterProvider());

Use in master:
```
ViewBag.MasterPageViewModel
```

This way you have fine uncoupled architecture. Of course you can combine it with Dependency Injection (we do, but I left it out for clarity) and configure your action filter for every action whichever way you want.

回答2:

In this case you can use ViewBag.

public ActionResult Index(UserData userData)
{
    AccountLoginWidgetVM model = new AccountLoginWidgetVM();
    if (null != userData)
        model.UserData = userData;

    ViewBag.UserData = userData;
    return View(userData);
}


@Html.RenderPartial("LoginPartial", ViewBag.UserData)

You have to make sure that userData is not null. If it'll be null the passed model will be default model of the view.

来源：https://stackoverflow.com/questions/11739905/how-do-i-pass-value-to-mvc3-master-page-layout

标签

asp.net-mvc

asp.net-mvc-3

model-binding