验证失败时的MVC 5剃刀处理视图

Question

I have an MVC Razor layout with a WebGrid.

@Html.ValidationSummary()
<div>

    @model List<DelsDTO>   

    @{
        var grid = new WebGrid(Model, defaultSort: "Name");
    }

    @grid.GetHtml(headerStyle: "webgrid-header", columns: grid.Columns(

    grid.Column(header: "Select", format: @<text><input name="checkedDelUnits" type="checkbox" value="@item.delId" /></text>),
    grid.Column("DelId", header: "ID"),
    grid.Column("Name", style: "nameColLen"),
    grid.Column("CRate", header: "C Rate", style: "span1", format: (item) => 
        (item.CRate == null) ? String.Empty : String.Format("{0:0.00}", @item.CRate))
     )
     )

    <td><input type="submit" name="saveChanges" value="Save Changes" /></td>
 }
</div>

Using a submit button I perform validation checks in a controller method. If the validation fails I set:

ModelState.AddModelError("", "No records Selected");
return View("Search");

At this point I have no datasource for the view so it is returned with an empty grid. What is best practice for handling this?

Should I pass the webgrid datasource (model) from the view to the controller only to pass it back if validation fails? If so how do that?

Answer 1

If the validation fails you basically need to create the model once again since it is not saved anywhere. So if on the initial action you were doing something like (just an idea below):

var model = GetGridModel();
return View("Search", model);

You would need to do the same on submit when validation failed:

ModelState.AddModelError("", "No records Selected");
var model = GetGridModel();
return View("Search", model);