Retaining Form Values After Post (not part of mode

问题:

I have a MVC4 page that has a form with a collection of checkboxes, radio buttons and textboxes used as the search fields. Upon post the selections are parsed and the lower results grid is updated with new results. Right now all the form values are wiped out upon return and the new results are displayed in the grid - only the grid is part of the model.

I want all the form selections to retain their values after post so the user can see (and change) the selections for next post/search. The form is popuplated with viewbags.

@using (Html.BeginForm("Index", "Home", FormMethod.Post, new { id = "searchform" }))
{
    @Html.ValidationSummary("Please correct the following errors")

<div style="float:left;">

    <div style="float:left;">
    <label>Name:</label>
    @Html.TextBox("name")
    </div>

    <div style="float:left; margin-left:15px">
    <label>Company:</label>
    @Html.TextBox("company")
    </div>

    <div style="float:left; margin-left:65px">
    <label>Date Range:</label>
    @Html.TextBox("dateStart", "", new { @class = "datefield", type = "date" })
    &nbsp;to&nbsp;
    @Html.TextBox("dateEnd", "", new { @class = "datefield", type = "date" })
    </div>

</div>

<div style="clear: both;">
    Match Any Categories? <input type="radio" name="categoryMatchAll" value="false" checked="checked" />&nbsp;&nbsp;&nbsp;
    Match All Categories?  <input type="radio" name="categoryMatchAll" value="true" /> 
</div>

<div style="float:left;">

    <div id="searchform-categories" style="float:left;">
        <div class="scroll_checkboxes">
            <label>Categories</label>
            <ul>
            @foreach (var x in ViewBag.Categories)
            {
                    <li>
                        <input type="checkbox" name="categories" value="@x.Id"/>

                        @x.Name

                    </li>
            }
            </ul>
        </div>
    </div>

    <div id="searchform-diversity" style="float:left; margin-left:30px">    
        <div class="search-selection" style="float:left;">
            <label>Minority Owned</label>
            <ul>
                @foreach (var x in ViewBag.Minorities)
                {
                    <li>
                        @Html.RadioButton("minorities", (String)x.Id.ToString())
                        @x.Name
                    </li>
                }
            </ul>
        </div>
        <div class="search-selection" style="float:left;">
            <label>Diversity Class</label>
            <ul>
            @foreach (var x in ViewBag.Classifications)
            {
                <li>
                    @Html.RadioButton("classifications", (String)x.Id.ToString())
                    @x.Name
                </li>
            }
        </ul>
        </div>    
    </div>  

</div>    

<div style="clear: both;">
    <input type="submit" value="Search Profiles" />
    <input type="submit" value="Reset" />
    </div>       
}

the data grid is bound to the model as

@model IEnumerable<VendorProfileIntranet.Models.VendorProfile>

<table id="VendorTable" width="100%" class="gradeA">
<thead>
    <tr>
    <th>
        @Html.DisplayNameFor(model => model.Name)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.CompanyName)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.City)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.State)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.DateCreated)
    </th>
    <th>Actions</th>
    </tr>
</thead>
<tbody>

@foreach (var item in Model)
{
<tr>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.Name)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.CompanyName)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.City)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.State)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.DateCreated)
    </td>
    <td class="list-field">
        @Html.ActionLink("Edit", "Edit", new { id = item.ProfileID }) |
        @Html.ActionLink("View", "View", new { id = item.ProfileID }) |
        @Html.ActionLink("Delete", "Delete", new { id = item.ProfileID }, new { onclick = " return DeleteConfirm()" })
    </td>
</tr>

}

</tbody>
<tfoot>
    <tr>
        <td>&nbsp;</td>
    </tr>
</tfoot>

回答1:

So here is how I typically solve this problem. My notes are purely my opinion (religous?) about naming classes in an MVC project to keep clear their purpose.

Couple of interfaces to keep it extensible:

// be specific about what type of results, both in the name of the 
// interface and the property needed, you don't want to have overlapping
// properies on your classes, I like suffixing interfaces that are specific
// to a View or Partial View with View
public interface IPersonSearchResultsView
{
   IEnumerable<EFPerson> PersonSearchResults { get; }
}

public interface IPersonSearchCriteriaView
{
  PersonSearchCriteriaModel PersonSearchModel { get; }
}

Couple of classes

// I like suffixing classes that I only use for MVC with Model
public PersonSearchCriteriaModel
{
  public string Name {get; set;}  
  public string Company {get; set;}
  public string DateStart {get; set;}
  public string DateEnd {get; set;}
}

// I like suffixing classes that I used passed to a View/Partial View
// with ViewModel    
public class PersonSearchViewModel : IPersonSearchResultsView, 
                                     IPersonSearchCriteriaView
{
  public IEnumerable<EFPerson> PersonSearchResults { get; set; }
  public PersonSearchCriteriaModel PersonSearchModel { get; set; }
}

Now for your controllers, I'll set them up in a way that would also allow you to do Ajax in the future.

public PersonController : Controller
{
  public ActionResult Search()
  {
    var model = new PersonSearchViewModel();
    // make sure we don't get a null reference exceptions
    model.PersonSearchModel = new PersonSearchCriteriaModel ();
    model.PersonSearchResults = new List<EFPerson>();
    return this.View(model);
  }

  [HttpPost]
  public ActionResult Search(PersonSearchViewModel model)
  {
    model.PersonSearchResults = this.GetPersonResults(model.PersonSearchModel);

    return this.View(model)
  }

  // You could use this for Ajax
  public ActionResult Results(PersonSearchViewModel model)
  {
    model.PersonSearchResults = this.GetPersonResults(model.PersonSearchModel);

    return this.Partial("Partial-SearchResults", model)
  }

  private GetPersonResults(PersonSearchCriteriaModel criteria)
  {
    return DbContext.GetPersonResults(criteria)
  }
}

Create a couple of partial-views your Views.

/Views/Person/Partial-SearchCriteria.cshtml

@model IPersonSearchCriteriaView

// the new part is for htmlAttributes, used by Ajax later
@using (Html.BeginForm(..., new { id="searchCriteria" }))
{
  // Here is were the magic is, if you use the @Html.*For(m=>)
  // Methods, they will create names that match the model
  // and you can back back to the same model on Get/Post

  <label>Name:</label>
  @Html.TextBoxFor(m => Model.PersonSearchModel.Name)

  // or let mvc create a working label automagically

  @Html.EditorFor(m => Model.PersonSearchModel.Name)

  // or let mvc create the entire form..

  @Html.EditorFor(m => Model.PersonSearchModel)
}

/Views/Person/Partial-SearchResults.cshtml

@model IPersonSearchResultsView

@foreach (var person in Model.PersonSearchResults )
{
  <tr>
    <td class="list-field">
      @Html.DisplayFor(modelItem => person.Name)
   </td>

   // etc
  </tr>
 }

And Finally the view:

/Views/Person/Search.cshtml

@model PersonSearchViewModel 

@Html.Partial("Partial-SearchCriteria", Model)

// easily change the order of these

<div id="searchResults">
@Html.Partial("Partial-SearchResults", Model);
</div>

Now enabling Ajax is pretty crazy easy (simplified and my not be exactly right):

$.Ajax({
  url: '/Person/Results',
  data: $('#searchCriteria').serialize(),
  success: function(jsonResult)
  {
    $('#searchResults').innerHtml(jsonResult);
  });

回答2:

if you are using html in mvc then check solution 2 from here, value="@Request["txtNumber1"]" worked fine for me,

<input type="text" id="txtNumber1" name="txtNumber1" value="@Request["txtNumber1"]"/>

hope helps someone.

回答3:

What I typically do is pass the posted Model back into the view. This way the values are not cleared out.

Your code would look something like this:

<div style="float:left;">

    <div style="float:left;">
    <label>Name:</label>
    @Html.TextBox("name", Model.Name)
    </div>

<div style="float:left; margin-left:15px">
<label>Company:</label>
@Html.TextBox("company", Model.Company)
</div>

<div style="float:left; margin-left:65px">
<label>Date Range:</label>
@Html.TextBox("dateStart", Model.DateStart, new { @class = "datefield", type = "date" })
&nbsp;to&nbsp;
@Html.TextBox("dateEnd", Model.DateEnd, new { @class = "datefield", type = "date" })
</div>

When initially getting the form, you'll have to create a new Model, otherwise the Model will be null and throw an exception when properties are called on it.

Sample Model

public class SearchModel
{

    public SearchModel()
    {
        Results = new List<Result>();
    }

    public string Name {get; set;}  

    public string Company {get; set;}

    public string DateStart {get; set;}

    public string DateEnd {get; set;}

    public List<Result> Results {get; set;}
}


@foreach (var item in Model.Results)
{
<tr>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.Name)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.CompanyName)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.City)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.State)
    </td>
    <td class="list-field">
        @Html.DisplayFor(modelItem => item.DateCreated)
    </td>
    <td class="list-field">
        @Html.ActionLink("Edit", "Edit", new { id = item.ProfileID }) |
        @Html.ActionLink("View", "View", new { id = item.ProfileID }) |
        @Html.ActionLink("Delete", "Delete", new { id = item.ProfileID }, new { onclick = " return DeleteConfirm()" })
    </td>
</tr>

}

Here is a link on creating models for a view in MVC.