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Danilo
Asked: 2020-01-09 07:44:38 +0800 CST 2020-01-09 07:44:38 +0800 CST

How to return a query from the controller to a view that already has data

  • 772

In a view, I have a list of data that is loaded into a table (grid type) and inside it I need to call a controller method to get more data through a url.action. This is how I have the data in the view:

<% For Each item In Model.listadoNoticias%>
<tr>
  <td>
    <%: Html.DisplayFor(Function(modelItem) item.TituloNoticia)%>
  </td>
  <td>
    <%: Html.DisplayFor(Function(modelItem) item.DescripcionNoticia)%>
  </td>
  <td>
    <%: Url.Action("Datos", "Noticias", New With {.id = item.IdNoticia})%>'                                
  </td>  
</tr><% Next%>

In the url action to the controller so that data that comes from a query appears. In the controller:

Function Datos (ByVal id As Integer) As ActionResult
   Using db As New BD_Prueba
   Dim datos = (From t3 In db.FOTO From intermedia In t3.NOTICIA.Where(Function(x) x.IdNoticia = id) Select New With {t3.NombreFoto}).ToList()
    End Using

    Return View(datos)

End Function

I imagine that instead of go it ActionResultshould be something like List(Of String)and instead of Return View(datos), it should be something like Return list(fotos). I would like to know what this fix would look like in the controller, since I need to return a list of data to the action url of the view.

And I would like to add another question, if instead of returning a list of strings, I had to return a list of binary files, how would it be in that case too?

asp.net-mvc-5

2 Answers

  1. If what you want is to inject a string or html into the table, you should not use the Url.Action(), but it should be the Html.Action():

    <td>
  <%: Html.Action("Datos", "Noticias", New With {.id = item.IdNoticia})%>'                                
</td>

    In this way, what the action returns will be rendered in that place.

    You can make the action return a simple string if you need to, although I notice you create a generated list from linq, you may need to convert it, if you have a list of strings you could use the String.Join()to concatenate the values ​​separated by a character

    A clarification, remember that there is the Html.Action()and theHtml.RenderAction()

    Html.RenderAction and Html.Action

    • 0
  2. Best Answer

    The use of the string.join could be like

    Function Datos (ByVal id As Integer) As String

Using db As New BD_Prueba
    Dim datos As List(Of String) = (From t3 In db.FOTO From intermedia In t3.NOTICIA.Where(Function(x) x.IdNoticia = id) Select New With {t3.NombreFoto}).ToList()

    Return String.Join(", ", datos)
End Using

End Function
    • 0