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MVC posting with a list of objects, collection is empty

2018-02-13 02:55 andrewb imported from Stackoverflow

I am making a kind of walkthrough (step 1 > 2 > 3 etc) and one of the last steps is to select an item from a select list.

The view where the user selects from the select list has this model

public class EventAndCompany
{
    public int EventID { get; set; }
    public int CompanyID { get; set; }
}

And the view is

@model Prototypes.Models.EventAndCompany

<div class="row">
    <div class="col-md-4">
        <h2>Step 3. Select questionnaire(s)</h2>
        @using (Html.BeginForm("Step4", "Home", FormMethod.Post))
        {
            @Html.AntiForgeryToken()
            @Html.HiddenFor(m => m.EventID)
            @Html.HiddenFor(m => m.CompanyID)
            <select name="Questionnaires">
                <option value="58926211-517E-4F5E-8E77-6256EC1832F6">Questionnaire 1</option>
                <option value="7477ECB1-C548-4532-9D07-C01DA50A5B2C">Questionnaire 2</option>
                <option value="EBE4D377-BF46-478B-AEF7-E8F853B8632C">Questionnaire 3</option>
                <option value="D94B7639-AF26-4CBE-A792-DCD7AC034BFB">Questionnaire 4</option>
                <option value="46544CFE-75A5-446B-8E6F-DB4E54B86890">Questionnaire 5</option>
            </select>
            <p><input type="submit" class="btn btn-default" value="Submit" /></p>
        }
    </div>
</div>

And the action, they are submitting to, has this method signature

public ActionResult Step4(Models.EventCompanyQuestionnaires model)

And that model is

public class EventCompanyQuestionnaires
{
    public int EventID { get; set; }
    public int CompanyID { get; set; }
    public List<Questionnaire> Questionnaires { get; set; }
}

Questionnaire is

public class Questionnaire
{
    public Guid QuestionnaireID { get; set; }
}

When I submit the form to Step4 action, the Questionnaires model field is initialized, but the Count is 0 and the selected option in the select is not passed to the controller.

1 answer

  • answered 2018-02-13 08:10 Saad Qais

    just modify your post action to 

    public ActionResult Step4(Models.EventCompanyQuestionnaires model, Guid Questionnaires)

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