Why is my model's data being cleared at POST

Question

I'm sorry if this ends up simple or stupid question, I'm very new to MVC and Razor, being dropped in deep end with no formal training on anything current...

I don't understand why the data in my model is available in my first view is not available in my second view.

Controller initiates an instance of model using code

Product _Product = new Product();

then the first view is called after a bunch of initial data queries have ran. The view is called using

return View("Attributes", _Product)

to call the view passing it the _Product instance of model.

My first view does many things but relevant to this question it shows a table using foreach row on dataset filled by SQL on controller stored on model.

@foreach(DataRow row in Model.attList.Tables[0].Rows)

The view has multiple buttons, such as add, delete, edit... Each have their own action assigned such as

<input type="submit" class="btn btn-primary" name="action:btnDelete" value="Delete" />

If the user presses one of the buttons on that view that triggers HTTPPOST. One of them calls a new view but if I pass my model to that view again, the data is now blank? I am passing the model to the view, and accepting it in HTTPPOST and passing it to the next view (or so I thought).

I'm using very generic beginning to form

@using (Html.BeginForm()) {

The code in controller for this button is very basic

[HttpPost] 
[MultipleButton(Name = "action", Argument = "btnEditValues")] 
public ActionResult btnEditValues(Product _Product) 
{ 
    return View("btnEditValues", _Product); 
}

But then in that 2nd view if I try to re-display the same table, it now says my Model.attList is empty. I added quick script of console.log(@Model.attList); and when I click the button it is showing the 2nd view but the console is logging a blank value (not NULL, just blank)...

I'm sure I'm just missing something simple - or perhaps I'm trying to do something I can't ???

---

The following was copied/pasted, without edit, into this question from an errantly posted "answer" which was intended to be an edit on the question. The answer has been flagged and should be removed.

Per David's Request.

Here is complete M, V, V, and C (didn't include other 2 views they don't use Model and both work)...

!!! NOTE !!!: This code is being used somewhere everyone has SQL manager and Admin rights to SQL server. As such SQL parameters were not used. This code would be vulnerable to SQL injection if used on open Website.

Model

namespace P21.Rules.Visual.Areas.KCDA_ItemMaint_Attributes.Models
{
    public class Product
    {
        // Variables used between views
        public int RowSelected { get; set; }

        // Declare datasets to use as list
        public DataSet attList { get; set; }
        public DataSet lowList { get; set; }
    }
}

Controller

namespace P21.Rules.Visual.Areas.KCDA_ItemMaint_Attributes.Controllers
{
    #region Multiple Buttons
    [AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
    public class MultipleButtonAttribute : ActionNameSelectorAttribute
    {
        public string Name { get; set; }
        public string Argument { get; set; }

        public override bool IsValidName(ControllerContext controllerContext, string actionName, MethodInfo methodInfo)
        {
            var isValidName = false;
            var keyValue = string.Format("{0}:{1}", Name, Argument);
            var value = controllerContext.Controller.ValueProvider.GetValue(keyValue);

            if (value != null)
            {
                controllerContext.Controller.ControllerContext.RouteData.Values[Name] = Argument;
                isValidName = true;
            }

            return isValidName;
        }
    }
    #endregion


    public class KCDA_ItemMaint_AttributesController : BaseRuleController
    {
        #region public variables
        // public dataset for loading SQL values
        DataSet attload = new DataSet();
        DataSet lowload = new DataSet();
        #endregion

        #region Main Action
        // GET: KCDA_ItemMaint_Attributes/KCDA_ItemMaint_Attributes
        public ActionResult Attributes()
        {

            if (Data.Fields["item_id"].FieldValue == string.Empty)
            {
                // Report error and prevent form pop-up if no product group has been selected
                Rule.RuleResult.Success = false;
                Rule.RuleResult.Message = "You must first select an Item before listing Attributes";
                return RedirectToAction("Close", "Initialize", new { area = "" });
            }
            else
            {

                try
                {
                    // Create container and setup Group values
                    Product _Product = new Product();

                    //Get Attributes for selected item
                    LoadAttributes();
                    _Product.attList = attload.Copy();

                    //Get ECom Server Side Attribute for selected item
                    LoadLower();
                    _Product.lowList = lowload.Copy();

                    return View("Attributes", _Product);

                }
                catch (Exception ex)
                {
                    //catch the error and send it to the Error view with the HandleErrorInfo
                    return View("Error", new HandleErrorInfo(ex, "KCDA_ItemMaint_Attributes", "Attributes"));
                }

            }
        }
        #endregion

        #region Buttons
        [HttpPost]
        [MultipleButton(Name = "action", Argument = "btnDelete")]
        public ActionResult btnDelete(Product _Product)
        {
            // create SQL command to delete the 
            string sqlDelete = "UPDATE BL_ProductAttribute SET DeleteFlag = '1' WHERE [KEY] = '" + _Product.RowSelected + "'";

            // Run the sqlDELETE command
            SqlCommand cmdDelete = new SqlCommand(sqlDelete, P21SqlConnection);
            cmdDelete.ExecuteNonQuery();
            SqlDataAdapter daDelete = new SqlDataAdapter(cmdDelete);

            return View("btnDelete", _Product);
        }

        [HttpPost]
        [MultipleButton(Name = "action", Argument = "btnAdd")]
        public ActionResult btnAdd(Product _Product)
        {
            // Retrieve selected/loaded drop-down values
            string ddGroup = Request["ApplyGroup"];
            string ddName = Request["AttributeName"];
            string ddValue = Request["AttributeValue"];

            if (ddValue == "")
            {
                ViewBag.msg = "No Value Selected";
            }
            else
            {
                // default duplicate count to 0
                int duplicate = 0;

                // create SQL command to check for duplicate attribute 
                string sqlDuplicate = "SELECT COUNT(1) FROM BL_ProductAttribute " +
                                      "WHERE SKU = '" + Data.Fields["item_id"].FieldValue + "' " +
                                      "AND AttributeGroupName = '" + ddGroup + "'";

                // Run the sqlDuplicate command
                SqlCommand cmdDuplicate = new SqlCommand(sqlDuplicate, P21SqlConnection);
                cmdDuplicate.CommandType = CommandType.Text;
                SqlDataAdapter daDuplicate = new SqlDataAdapter(cmdDuplicate);

                // Create dataset from duplicate check
                DataTable dupcheck = new DataTable();
                daDuplicate.Fill(dupcheck);

                // Set count if exists
                duplicate = int.Parse(dupcheck.Rows[0][0].ToString());

                // if exists update/undelete otherwise insert
                if (duplicate > 0)
                {
                    // create SQL command to update the attribute 
                    string sqlAdd = "UPDATE BL_ProductAttribute " +
                                    "SET BL_ProductAttribute.Value = '" + ddValue.Replace("'", "''") + "', " +
                                    "BL_ProductAttribute.AttributeTitle = '" + ddName + "', " +
                                    "BL_ProductAttribute.DeleteFlag = 0, " +
                                    "BL_ProductAttribute.ProductID = '" + Data.Fields["product_group_id"].FieldValue + "' " +
                                    "FROM BL_ProductAttribute " +
                                    "WHERE SKU = '" + Data.Fields["item_id"].FieldValue + "' AND AttributeGroupName = '" + ddGroup + "' ";

                    // Run the sqlAdd command
                    SqlCommand cmdAdd = new SqlCommand(sqlAdd, P21SqlConnection);
                    cmdAdd.ExecuteNonQuery();
                    SqlDataAdapter daAdd = new SqlDataAdapter(cmdAdd);

                    ViewBag.msg = "Record Updated";
                }
                else
                {
                    // If adding determine next key value for unique ID
                    string newKey = string.Empty;

                    // create SQL command to get next KEY value for insert reset current maxkey
                    string sqlMax2 = "SELECT max([key])+1 FROM BL_AttributeEnumValue";

                    // Run the sqlMax command
                    SqlCommand cmdKey2 = new SqlCommand(sqlMax2, P21SqlConnection);
                    cmdKey2.CommandType = CommandType.Text;
                    SqlDataAdapter daKey2 = new SqlDataAdapter(cmdKey2);

                    // Create dataset from newKey check and assign to newKey 
                    DataTable KeyCheck2 = new DataTable();
                    daKey2.Fill(KeyCheck2);
                    newKey = KeyCheck2.Rows[0][0].ToString();

                    // create SQL command to update the attribute 
                    string sqlAdd = "INSERT INTO BL_ProductAttribute ([Key], ProductId, SKU, AttributeTitle, " +
                                    "isSKUlevel, isRequired, isDefault, Value, AttributeGroupName, DeleteFlag) " +
                                    "VALUES('" + newKey + "', '" + Data.Fields["product_group_id"].FieldValue + "', '" +
                                    Data.Fields["item_id"].FieldValue + "', '" + ddName + "', 1, 1, 1, '" +
                                    ddValue.Replace("'", "''") + "', '" + ddGroup + "', 0)";

                    // Run the sqlAdd command
                    SqlCommand cmdAdd = new SqlCommand(sqlAdd, P21SqlConnection);
                    cmdAdd.ExecuteNonQuery();
                    SqlDataAdapter daAdd = new SqlDataAdapter(cmdAdd);

                    ViewBag.msg = "Record Added";
                }

            }

            return View("btnAdd", _Product);
        }

        [HttpPost]
        [MultipleButton(Name = "action", Argument = "btnEditValues")]
        public ActionResult btnEditValues(Product _Product)
        {
            return View("btnEditValues", _Product);
        }
        #endregion

        #region SQL Loads
        private void LoadAttributes()
        {          
            // Define SQL select command
            string sqlAttributes = "SELECT * FROM BL_ProductAttribute " +
                                   "WHERE SKU = '" + Data.Fields["item_id"].FieldValue + "' AND DeleteFlag = '0' " +
                                   " AND AttributeGroupName in ('SKU_Color', 'SKU_SelectableAttribute_1', 'SKU_SelectableAttribute_2')";

            // Set SQL command type to text and run it
            SqlCommand cmdlist = new SqlCommand(sqlAttributes, P21SqlConnection);
            cmdlist.CommandType = CommandType.Text;
            SqlDataAdapter dalist = new SqlDataAdapter(cmdlist);

            // Load results from SQL into DataSet
            dalist.Fill(attload);
        }

        private void LoadLower()
        {           
            string DBconn = "vsldb1";

            // Define SQL select command
            string sqllist = "SELECT [Key], ProductID, SKU, AttributeTitle, isSKUlevel, isRequired, isDefault, " +
                                    "\"Value\" = Case " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '0') then '0 - Warehouse Regular Item' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '1') then '1 - Not on Website/Pending' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '2') then '2 - RFQ' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '3') then '3 - Limited Quote' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '4') then '4 - Discontinued/Obsolete' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '5') then '5 - Specials' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '6') then '6 - Direct Ship' " +
            "when (AttributeTitle = 'KCDASKUStatus' and ltrim(convert(varchar,Value)) = '7') then '7 - Offline' " +
            "else value end, AttributeGroupName, UpdateFlag  FROM OPENDATASOURCE('SQLOLEDB','Data Source=" + DBconn + ";user " +
                                   "id=sa;password=KCDAAdmin').KCDA.dbo.KCDA_ProductAttribute PA" +
                                   " WHERE PA.SKU = '" + Data.Fields["item_id"].FieldValue + "' AND PA.AttributeGroupName not in " +
                                   "('SKU_Color', 'SKU_SelectableAttribute_1', 'SKU_SelectableAttribute_2')";

            // Set SQL command type to text and run it
            SqlCommand cmdlist = new SqlCommand(sqllist, P21SqlConnection);
            cmdlist.CommandType = CommandType.Text;
            SqlDataAdapter dalist = new SqlDataAdapter(cmdlist);

            // Load results from SQL into DataSet
            dalist.Fill(lowload);
        }
        #endregion

        #region Drop Downs
        [HttpPost]
        public ActionResult GetAttributeNames(string selectedOption)
        {

            // Define variables for JSON query to use
            JsonResult result = new JsonResult();
            List<string> attNames = new List<string>();
            List<string> attValues = new List<string>();

            if (selectedOption != null)
            {
                // SQL to get attribute name for the selected attribute group for this product group 
                string sql = "SELECT Title FROM BL_Attribute (NOLOCK) WHERE BL_Attribute.DeleteFlag = '0' AND BL_Attribute.AttributeGroupName = '" + selectedOption + "'" +
                                 " AND BL_Attribute.Title in (select AD.AttributeTitle from BL_AttributeDept AD where AD.product_group_id = '" + Data.Fields["product_group_id"].FieldValue.Substring(0, 2) +"')";

                using (SqlCommand selectAttNames = new SqlCommand(sql, P21SqlConnection))
                {
                    using (SqlDataReader reader = selectAttNames.ExecuteReader())
                    {
                        while (reader.Read())
                        {
                            attNames.Add(reader["Title"].ToString());
                        }            
                    }
                }

                // SQL to get list of current available values for this attribute type
                string sql2 = "SELECT Value FROM BL_AttributeEnumValue (NOLOCK) WHERE DeleteFlag = '0' and AttributeTitle = '" + 
                              attNames[0] + "' ORDER BY Value";

                using (SqlCommand selectAttValues = new SqlCommand(sql2, P21SqlConnection))
                {
                    using (SqlDataReader reader2 = selectAttValues.ExecuteReader())
                    {
                        while (reader2.Read())
                        {
                            attValues.Add(reader2["Value"].ToString());
                        }
                    }
                }

                // define return object 
                var retObj = new
                {
                    retNames = attNames,
                    retValues = attValues
                };
                return Json(retObj, JsonRequestBehavior.AllowGet);

            }

            return Json(new { Success = "false" });
        }


        #endregion

        #region Edit Values



        #endregion

        #region Close Rule
        [HttpPost]
        public ActionResult Return()
        {
            Rule.RuleResult.Success = true;

            //IMPORTANT - This is what returns the Visual Rule control back to the server
            //DO NOT REMOVE
            return RedirectToAction("Close", "Initialize", new { area = "" });
        }
        #endregion
    }

}

Attributes View

@using P21.Rules.Visual.Areas.KCDA_ItemMaint_Attributes.Models
@using System.Data


@model Product


@{
    ViewBag.Title = "Attributes";
    Layout = "~/Views/Shared/_VisualRuleLayout.cshtml";

    var listAttGroups = new List<SelectListItem>
    {
        new SelectListItem { Text = "SKU_Color", Value = "SKU_Color"},
        new SelectListItem { Text = "SKU Select Att 1", Value = "SKU_SelectableAttribute_1"},
        new SelectListItem { Text = "SKU Select Att 2", Value = "SKU_SelectableAttribute_2"}
    };
}

@section scripts{
    <script>
        $(function () {
            $("#ApplyGroup").change(function () {
                var option = $(this).val();

                //Clear and activate 2nd and 3rd drop down
                $("#AttributeName").empty();
                $("#AttributeValue").empty();
                $("#AttributeName").prop('disabled', false);
                $("#AttributeValue").prop('disabled', false);

                var url = "GetAttributeNames?selectedOption=" + option;

                $.post(url, function (retObj) {
                    $.each(retObj.retNames, function (i, attName) {
                        $("#AttributeName").append($('<option></option>').val(attName).html(attName));
                    });
                    $.each(retObj.retValues, function (i, attValue) {
                        $("#AttributeValue").append($('<option></option>').val(attValue).html(attValue));
                    });
                });
            });
        });
    </script>
}

@using (Html.BeginForm())
{
        <div class="container">
        <div class="row">
            <label class="col-md-3 control-label" for="ApplyGroup" id="lblApplyGroup">Attribute Group</label>
            <label class="col-md-3 control-label" for="AttributeName" id="lblAttributeName">Attribute Name</label>
            <label class="col-md-2 control-label" for="AttributeValue" id="lblAttributeValue">Attribute Value</label>
            <div class="col-md-2">
                <input type="submit" class="btn btn-primary" name="action:btnEditValues" value="Edit Values" />
            </div>
        </div>
        <div class="row" style="padding-top:5px">
            <div class="col-md-3">
                @Html.DropDownList("ApplyGroup", listAttGroups, "Select Group", new { @id = "ApplyGroup", @class = "form-control" })
            </div>
            <div class="col-md-3">
                @Html.DropDownList("AttributeName", new List<SelectListItem>(), new { @id = "AttributeName", @class = "form-control", disabled = "disabled" })
            </div>
            <div class="col-md-3">
                @Html.DropDownList("AttributeValue", new List<SelectListItem>(), new { @id = "AttributeValue", @class = "form-control", disabled = "disabled" })
            </div>
            <div class="col-md-3">
                <span class="pull-right">
                    <input type="submit" class="btn btn-primary" name="action:btnAdd" value="Add\Update" />
                </span>
            </div>
        </div>
        <div class="row" style="padding-top:20px">
            <div class="col-md-10">

            </div>
            <div class="col-md-2">
                <span class="pull-right">
                    <input type="submit" class="btn btn-primary" name="action:btnDelete" value="Delete" />
                </span>
            </div>
        </div>

        <div class="row" style="padding-top:10px">
            <div class="col-md-12">
                <table id="attTable" style="width:100%" cellpadding="0" cellspacing="0" border="1" class="row">
                    <tbody>
                        <tr style="background-color: #F0F8FF;">
                            <th></th>
                            <th>Dept</th>
                            <th>Item #</th>
                            <th>Attribute Name</th>
                            <th>SKU Level</th>
                            <th>Required</th>
                            <th>Default</th>
                            <th>Attribute Value</th>
                            <th>Attribute Group</th>
                        </tr>
                        @foreach (DataRow row in Model.attList.Tables[0].Rows)
                        {
                            <tr class="selectable-row">
                                <td>@Html.RadioButtonFor(m => Model.RowSelected, row[0])</td>
                                <td>@row[1]</td>
                                <td>@row[2]</td>
                                <td>@row[3]</td>
                                <td>@row[4]</td>
                                <td>@row[5]</td>
                                <td>@row[6]</td>
                                <td>@row[7]</td>
                                <td>@row[8]</td>
                            </tr>
                        }
                    </tbody>
                </table>
            </div>
        </div>

        <div class="row" style="padding-top:50px">
            <div class="col-md-12">
                <table id="lowTable" style="width:100%" cellpadding="0" cellspacing="0" border="1" class="row">
                    <tbody>
                        <tr style="background-color: #F0F8FF;">
                            <th>Dept</th>
                            <th>Item #</th>
                            <th>Attribute Name</th>
                            <th>SKU Level</th>
                            <th>Required</th>
                            <th>Default</th>
                            <th>Attribute Value</th>
                            <th>Attribute Group</th>
                        </tr>
                        @foreach (DataRow row in Model.lowList.Tables[0].Rows)
                        {
                            <tr class="selectable-row">
                                <td>@row[1]</td>
                                <td>@row[2]</td>
                                <td>@row[3]</td>
                                <td>@row[4]</td>
                                <td>@row[5]</td>
                                <td>@row[6]</td>
                                <td>@row[7]</td>
                                <td>@row[8]</td>
                            </tr>
                        }
                    </tbody>
                </table>
            </div>
        </div>
    </div>
}

btnEditValues View

@using P21.Rules.Visual.Areas.KCDA_ItemMaint_Attributes.Models
@using System.Data


@model Product

@{
    ViewBag.Title = "btnEditValues";
    Layout = "~/Views/Shared/_VisualRuleLayout.cshtml";

    var listAttGroups = new List<SelectListItem>
    {
        new SelectListItem { Text = "SKU_Color", Value = "SKU_Color"},
        new SelectListItem { Text = "SKU Select Att 1", Value = "SKU_SelectableAttribute_1"},
        new SelectListItem { Text = "SKU Select Att 2", Value = "SKU_SelectableAttribute_2"}
    };
}

@section scripts{
    <script>
        console.log(@Model.attList);
    </script>
}

<p align="right"><button type="button" class="btn btn-primary" onclick="location.href='@Url.Action("Attributes", "KCDA_ItemMaint_Attributes")'">X</button></p>
<center><h2>Edit Item Attribute Availble Values</h2></center>

@using (Html.BeginForm())
{
    <div class="container">
        <div class="row">
            <label class="col-md-4 control-label" for="EditApplyGroup" id="lblEApplyGroup">Attribute Group</label>
            <label class="col-md-4 control-label" for="EditAttributeName" id="lblEAttributeName">Attribute Name</label>
        </div>
        <div class="row" style="padding-top:5px">
            <div class="col-md-4">
                @Html.DropDownList("EditApplyGroup", listAttGroups, "Select Group", new { @id = "EditApplyGroup", @class = "form-control" })
            </div>
            <div class="col-md-4">
                @Html.DropDownList("EditAttributeName", new List<SelectListItem>(), "Select Name", new { @id = "EditAttributeName", @class = "form-control", disabled = "disabled" })
            </div>
        </div>

        <div class="row" style="padding-top:10px">
            <div class="col-md-12">
                <table id="attEditTable" style="width:100%" cellpadding="0" cellspacing="0" border="1" class="row">
                    <tbody>
                        <tr style="background-color: #F0F8FF;">
                            <th></th>
                            <th>Attribute Value</th>
                            <th>Item Count</th>
                        </tr>
                    </tbody>
                </table>
            </div>
        </div>
    </div>
}

Answer 1

If your ultimate question is, "how can I post this model with all of it's data?",

public class Product
{
    // Variables used between views
    public int RowSelected { get; set; }

    // Declare datasets to use as list
    public DataSet attList { get; set; }
    public DataSet lowList { get; set; }
}

then the only real answer is "with a LOT of work." The answer that follows is probably mostly opinionated, so not really a great SO answer, but reflects my experience.

Basically, this controller action:

[HttpPost] 
[MultipleButton(Name = "action", Argument = "btnEditValues")] 
public ActionResult btnEditValues(Product _Product) 
{ 
    // ... other code

    return View("btnEditValues", _Product); 
}

expects the model binder to be able to construct an instance of the Product class. To do so, it needs to have every public property be present as a form value in the HTTP request that was made to this controller action. Those form values come from what are called successful controls, which is basically any form element (<input />, <select>, or <textarea>, generally) which has a name (the name="propertynamehere" attribute). If the field's not present, it's value doesn't exist.

Given how complex the DataSet class is, I would not recommend attempting to build enough form fields to successfully get your data back from the model binder. The only thing you really should care about is RowSelected - that lets you fetch the data you need from the database. Given that an SQL connection and query are generally pretty fast, it's probably a better user experience, as well, since posting enough data to repopulate a DataSet requires A LOT of form values (you might even run into a issue with exceeding the maximum allowed number of fields, although that is configurable in ASP.NET). If that makes sense and sounds feasible, I can elaborate on how to refactor at least this action to match how MVC is intended to work.

As a note, if the goal is to take a user to an edit page, that makes more sense as a GET request; loading an edit screen is an idempotent action, which matches the semantics of a GET. POST is normally meant to be used to update values, which you're not doing there.

You might find this useful, as it describes the recommended pattern to follow (PRG, or POST-Redirect-GET): https://en.wikipedia.org/wiki/Post/Redirect/Get

Of course, if the material you're learning from is on the older side, ASP.NET (via WebForms) used POST to transfer something called ViewState, which was/is used to give the illusion of state within a web application - the idea was "Windows Forms for the Web", but it adds a lot of overhead that you really don't want in a modern aplication. Given your background, it (WebForms) might be a better fit, though, since it lets you focus on an event-driven development model.

Answer 2

The form doesn't have any data for constructing the model.

Take a step back and consider the HTTP requests being made. An HTML <form>, when submitted, requests the action URL (as a POST request in this case) and includes whatever form values are present in that form. This likely does not include disabled form elements. (I could be mistaken on that.) And it definitely does not include the HTML of the form.

(You've indicated that you didn't come from a WebForms background, but coincidentally enough this is a very common mistake for people who did.)

With the exception of the buttons, the only form elements I'm seeing are three drop down lists (ApplyGroup, AttributeName, AttributeValue) as well as the radio buttons being emitted in the loop, called RowSelected.

But the model needs more values to be created:

public int RowSelected { get; set; }

// Declare datasets to use as list
public DataSet attList { get; set; }
public DataSet lowList { get; set; }

The model has RowSelected, and you can debug to confirm if that value is being correctly populated. (Your question indicates only that you're trying to debug the presence of the DataSet properties, not the RowSelected property.)

But including all data from two DataSet properties would be much more complex. And, perhaps more to the point, would be entirely unnecessary. Take a step back and consider that you'd be filling the page with data that you don't expect the user to edit and then posting all of that data back to the server that it just came from.

In your action you can get that RowSelected property in a variety of ways. As a method argument, as a model property, or simply as you currently get form values in your other action methods:

string rowSelected = Request["RowSelected"];

You can use int.TryParse() to convert that to an integer value if needed. Though the SQL code you're using is concatenating strings so you may not need to anyway.

(Side note: It's good that you're already aware that SQL injection is a bad thing. Even though in your particular case it's not necessarily a security problem, please be aware that SQL injection is also a very common source of bugs. It's worth learning the correct way of doing things.)

If you can get the fully-populated model from the database using an identifier, that would be ideal. It's certainly easier to just pass around the identifier than it is to pass around an entire complex model, especially if you're not expecting the user to edit that model on that page.

All in all, it looks like you're simply expecting the entire model to be posted to the server when really all you're posting is the identifier for the model. Which, fortunately enough, is all you actually need. Just use that identifier to fetch the intended record.