asp.net-mvc 如何从控制器传递字符串消息以在 MVC 中查看
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/23477560/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to pass a string message from controller to view in MVC
提问by user3172140
I want to display a string message through a string variable by passing from controller to View.
我想通过从控制器传递到视图来通过字符串变量显示字符串消息。
Here is my controller code:
这是我的控制器代码：
public ActionResult SearchProduct(string SearchString)
{
FlipcartDBContextEntities db = new FlipcartDBContextEntities();
string noResult="Search Result Not Found";
var products = from p in db.Products select p;
if (!String.IsNullOrEmpty(SearchString))
{
products = products.Where(s => s.ProductName.StartsWith(SearchString));
return View(products);
}
else
{
return View(noResult);
}
// Here i want to display the string value ei Message to the view.
// 这里我想向视图显示字符串值 ei Message。
please guide me. Am new to MVC
请指导我。我是 MVC 的新手
回答by Brian Mains
Change your controller to:
将您的控制器更改为：
public ActionResult SearchProduct(string SearchString)
{
FlipcartDBContextEntities db = new FlipcartDBContextEntities();
string noResult="Search Result Not Found";
var products = from p in db.Products select p;
if (!String.IsNullOrEmpty(SearchString))
{
products = products.Where(s => s.ProductName.StartsWith(SearchString));
return View(products.ToList());
}
else
{
ViewBag.Message = noResult;
return View(new List,Product>());
}
You can pass the message from the server to the client via the ViewBag. Note that you have to return the same API from both sides of the if/else, so you can't pass a list of products one time and a string the other. In your view:
您可以通过 ViewBag 将消息从服务器传递到客户端。请注意，您必须从 if/else 的两侧返回相同的 API，因此您不能一次传递产品列表，而另一次传递一个字符串。在您看来：
if (ViewBag.Message != null)
{
<span>@ViewBag.Message</span>
}
Or don't do any of that and just put the message in the view based on the existence of a product list having items within the list.
或者不要做任何事情，只是根据列表中包含项目的产品列表的存在将消息放入视图中。
// Model = Products returned; must make sure list returned is not null
if (Model.Count > 0)
{
<span>Search Result not found</span>
}
Or even as another option you can create a model class:
或者甚至作为另一种选择，您可以创建一个模型类：
public class SearchModel
{
public List<Product> Products { get; set; }
public string EmptyMessage { get; set; }
}
And return this via your view method:
并通过您的视图方法返回它：
//if
return View(new SearchModel { Products = products });
//else
return View(new SearchModel { EmptyMessage = "Search result Not Found" });
