Why ViewData not work - telerik-grid

I have MVC2 view in which there is a grid and image button. When image button is clicked, it will pass the data of grid's currentPage, filter and orderBy fields ... to another controller. The code is,
<%# Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<MaintenanceEditableViewModel>" %>
"Image button"
<a href="<%: Url.Action("ExportToExcel", "ExportExcelButton", new { resourceId = ViewData["resourceId"], pagenum = ViewData["page"], orderBy = ViewData["orderBy"], filter = ViewData["filter"] }) %>">
<img src='<%: Url.Content("~/Content/Images/ExportExcelButton.gif") %>' /></a>
"Grid"
<%= Html.Telerik().Grid<MaintenanceAthletesResultsViewModel>()
.Name("Grid")
.TableHtmlAttributes(new { style = "font-size:8pt;" })
.HtmlAttributes(new { style = "height:335px" })
.DataKeys(k => k.Add(k2 => k2.ResultID))
.DataBinding(dataBinding => dataBinding.Ajax()
.Select("AthletesResultsAjax", "Maintenance")
...
"Action to initialize the grid in Maintenance controller"
public ActionResult AthletesResults(string id, bool editable)
{
ViewData["resourceId"] = id;
this._resourceBL.PopulateMaintenanceResourcesViewData(id, this.SelectedSport());
MaintenanceEditableViewModel model = new MaintenanceEditableViewModel { Editable = editable };
return View(model);
}
[GridAction]
public ActionResult AthletesResultsAjax(string id, int page, string orderBy, string filter)
{
List<MaintenanceAthletesResultsViewModel> model = null;
if (!string.IsNullOrEmpty(id))
{
ViewData["page"] = page;
ViewData["orderBy"] = orderBy;
ViewData["filter"] = filter;
model = this._resourceBL.GetMaintenanceAthletesResultsViewModel(int.Parse(id));
}
return View(new GridModel(model));
}
public ActionResult ExportToExcel(string resourceId, string pagenum, string orderBy, string filter)
The strange thing is that only ViewData["resourceId"] (set in initialization of view) is able to be passed. The 3 parameters, ViewData["page"], ViewData["orderBy"], ViewData["filter"] (set in grid ajax action) can not be passed. All 3 are null in ExportToExcel and so I think they are not correctly stored in ViewData (I am not sure how to check ViewData when image button is pressed). I am confused and need help on this.
Thanks

I don't see how/where you're sending those arguments into the AthletesResultsAjax action. The signature of the dataBinding.Ajax().Select() function you're using only specifies the action and the controller name. How is it going to know what those values are? You need to specify a routeValues object to send the appropriate data to the controller action. If you debug the code and put a breakpoint in your ajax action, do the actual values come through? I could be quite off here but I think your problem is more on this end than on how the data is being stored in the ViewData.

I think the problem is that ViewData is mainly used pass data from Controller to View and in your case you have Controller -> View -> Controller. I think Telerik Knowledge Base has a good solution how to provide additional data to your export action. Telerik Knowledge Base
<%= Html.ActionLink("Export to Excel", "Export", new { page = 1, orderBy = "~", filter = "~"}, new { id = "exportLink" }) %>
<script type="text/javascript">
function onDataBound() {
var grid = $(this).data('tGrid');
var $exportLink = $('#exportLink');
var href = $exportLink.attr('href');
href = href.replace(/page=([^&]*)/, 'page=' + grid.currentPage);
href = href.replace(/orderBy=([^&]*)/, 'orderBy=' + (grid.orderBy || '~'));
href = href.replace(/filter=(.*)/, 'filter=' + (grid.filterBy || '~'));
$exportLink.attr('href', href);
}
</script>
The script dynamically updates Export-links url when data is received & rendered (OnDataBound) to the screen. It should then bind nicely on the Controller side.
If you're more familiar with JavaScript then you should probably put an click event to the export button and make GET request in the JavaScript side. Then you don't have make that ugly looking url modifications.
I hope this helps!

Related

Copy From excel spread sheet into blazor app

I have a hosted Blazor WebAssembly application.
I need a strategy or a sample on how can I copy values from an excel spreadsheet and paste them into the application with a final goal to add them into my database through the existing API.
So the question here is this: what components should I paste the values into, and how should I handle the whole process:
excel > clipboard > Component > save in db
It was actually more difficult than I initially thought. I've created a repo. The result is this.
You can select any elements in Excel, copy them, focus the content of your Blazor page and paste it. As a simple view, it is displayed in a table.
Let's go through the solution.
Index.razor
#page "/"
<div class="form-group">
<label for="parser">Parser type</label>
<select class="form-control" id="parser" #bind="_parserType">
<option value="text">Text</option>
<option value="html">HTML</option>
</select>
</div>
<PasteAwareComponent OnContentPasted="FillTable">
#if (_excelContent.Any() == false)
{
<p>No Content</p>
}
else
{
<table class="table table-striped">
#foreach (var row in _excelContent)
{
<tr>
#foreach (var cell in row)
{
<td>#cell</td>
}
</tr>
}
</table>
}
</PasteAwareComponent>
<button type="button" class="btn btn-primary" #onclick="#( () => _excelContent = new List<String[]>() )">Clear</button>
#code
{
private IList<String[]> _excelContent = new List<String[]>();
...more content, explained later...
}
If you copy a selection from Excel into the clipboard, not a single text is copied, but multiple representations of the same content. In my experiment, it has been three different types.
I've built two different parser: ExcelHtmlContentParser and ExcelTextContentParser. Regarding the many different possibilities of what a cell content in Excel can be, my implementation is merely completed and should be seen as an inspiration. To see both parsers in action, you can choose between them by changing the value in the select box.
The PasteAwareComponent handles the interaction with Javascript. You can place any content inside this component. If this component (or any child) has focus, the paste event will be handled correctly.
<span #ref="_reference">
#ChildContent
</span>
#code {
private ElementReference _reference;
[Parameter]
public RenderFragment ChildContent { get; set; }
[Parameter]
public EventCallback<IEnumerable<IDictionary<String, String>>> OnContentPasted { get; set; }
[JSInvokable("Pasted")]
public async void raisePasteEvent(IEnumerable<IDictionary<String, String>> items)
{
await OnContentPasted.InvokeAsync(items);
}
}
The component handles the interoperation with javascript. As soon the paste events happen the EventCallback<IEnumerable<IDictionary<String, String>>> OnContentPasted is fired.
Potentially, there could be more than one element inside the clipboard. Hence, we need to handle a collection IEnumerable<>. As seen in the picture before, the same clipboard item can have multiple representations. Each representation has a mime-type like "text/plain" or "text/html" and the value. This is represented by the IDictionary<String, String> where the key is the mime-type, and the value is the content.
Before going into the details about the javascript interop, we go back to the Index component.
<PasteAwareComponent OnContentPasted="FillTable">
...
</PasteAwareComponent>
#code {
private async Task FillTable(IEnumerable<IDictionary<String, String>> content)
{
if (content == null || content.Count() != 1)
{
return;
}
var clipboardContent = content.ElementAt(0);
IExcelContentParser parser = null;
switch (_parserType)
{
case "text":
parser = new ExcelTextContentParser();
break;
case "html":
parser = new ExcelHtmlContentParser();
break;
default:
break;
}
foreach (var item in clipboardContent)
{
if (parser.CanParse(item.Key) == false)
{
continue;
}
_excelContent = await parser.GetRows(item.Value);
}
}
}
The index component uses this event callback in the method FillTable. The method checks if there is one element in the clipboard. Based on the selection, the parser is chosen. Each representation is checked in the next step if the chosen parser can parse it, based on the provided mime-type. If the right parser is found, the parser does its magic, and the content of the field _excelContent is updated. Because it is an EventCallback StateHasChanged is called internally, and the view is updated.
The text parser
In the text representation, Excel uses \r\n as the end of the row and a \t for each cell, even the empty ones. The parser logic is quite simple.
public class ExcelTextContentParser : IExcelContentParser
{
public String ValidMimeType { get; } = "text/plain";
public Task<IList<String[]>> GetRows(String input) =>
Task.FromResult<IList<String[]>>(input.Split("\r\n", StringSplitOptions.RemoveEmptyEntries).Select(x =>
x.Split("\t").Select(y => y ?? String.Empty).ToArray()
).ToList());
}
I haven't tested how this behavior changes if the content is more complex. I guess that the HTML representation is more stable. Hence, the second parser.
The HTML parser
The HTML representation is a table. With <tr> and <td>. I've used the library AngleSharp as HTML parser.
public class ExcelHtmlContentParser : IExcelContentParser
{
public String ValidMimeType { get; } = "text/html";
public async Task<IList<String[]>> GetRows(String input)
{
var context = BrowsingContext.New(Configuration.Default);
var document = await context.OpenAsync(reg => reg.Content(input));
var element = document.QuerySelector<IHtmlTableElement>("table");
var result = element.Rows.Select(x => x.Cells.Select(y => y.TextContent).ToArray()).ToList();
return result;
}
}
We are loading the clipboard content as an HTML document, getting the table and iterating over all rows, and selected each column.
** The js interop ***
#inject IJSRuntime runtime
#implements IDisposable
<span #ref="_reference">
#ChildContent
</span>
#code {
private ElementReference _reference;
private DotNetObjectReference<PasteAwareComponent> _objectReference;
protected override async Task OnAfterRenderAsync(bool firstRender)
{
await base.OnAfterRenderAsync(firstRender);
if (firstRender == true)
{
_objectReference = DotNetObjectReference.Create(this);
await runtime.InvokeVoidAsync("BlazorClipboadInterop.ListeningForPasteEvents", new Object[] { _reference, _objectReference });
}
}
public void Dispose()
{
GC.SuppressFinalize(this);
if (_objectReference != null)
{
_objectReference.Dispose();
}
}
}
The PasteAwareComponent component overrides the OnAfterRenderAsync life cycle, to invoke a js interop method. It has to be the OnAfterRenderAsync because before, the HTML reference wouldn't exist, and we need the reference to add the paste event listener. When the paste event occurred the javascript has to call this object, so we need to create a DotNetObjectReference instance. We implemented the IDisposable interface and disposing the reference correctly to prevent memory leaks.
The last part is the javascript part itself. I've created a file called clipboard-interop.js and placed it inside the wwwroot/js folder.
var BlazorClipboadInterop = BlazorClipboadInterop || {};
BlazorClipboadInterop.ListeningForPasteEvents = function (element, dotNetObject) {
element.addEventListener('paste', function (e) { BlazorClipboadInterop.pasteEvent(e, dotNetObject) });
};
We use the HTML reference to register an event listener for the 'paste' event. In the handling method, we create the object that is passed to the C# method.
BlazorClipboadInterop.pasteEvent =
async function (e, dotNetObject) {
var data = await navigator.clipboard.read();
var items = []; //is passed to C#
for (let i = 0; i < data.length; i++) {
var item = {};
items.push(item);
for (let j = 0; j < data[i].types.length; j++) {
const type = data[i].types[j];
const blob = await data[i].getType(type);
if (blob) {
if (type.startsWith("text") == true) {
const content = await blob.text();
item[type] = content;
}
else {
item[type] = await BlazorClipboadInterop.toBase64(blob);
}
}
}
}
dotNetObject.invokeMethodAsync('Pasted', items);
e.preventDefault();
}
When we are using js interop, we should use objects that are easy to serialize. In the case of a real blob, like an image, it would be based64-encoded string, otherwise just the content.
The solution used the navigator.clipboard capabilities. The user needs to allow it. Hence we see the dialog.

Interacting with Hidden Fields and Actions with Javascript

I am trying to figure out how to get values back and forth between an external javascript library and the Acumatica back end.
Currently I have 2 fields that are hidden (set to hidden on the PXUIField Attribute) and I am picking up their values successfully as follows:
function doSomething() {
var url = px_alls['txtUrl'].value;
var clientId = px_alls['txtClientID'].value;
}
However I am not having the same luck setting a hidden fields values and then posting the data to the back end in this way:
client.on('someEvent', (data) => {
px_alls['txtId'].value = data.id;
Save();
})
How can I accomplish this?
Thanks
-Kyle
Reading form fields from px_alls works fine but I was not able to automate saving.
I use action callback to send the values from JavaScript to an action defined in the Graph.
var ds = px_alls['ds'];
ds.executeCallback('TestAction', 'parameter value');
Then In the graph you can use the parameter value to update the document:
public PXAction<PrimaryDAC> TestAction;
[PXButton]
[PXUIField(DisplayName = "Test Action")]
public virtual IEnumerable testAction(PXAdapter adapter)
{
string parameterValue = adapter.CommandArguments;
// Update document here with parameter value
return adapter.Get();
}

#html.dropdown onchange event MVC5

I have a View with a dropdownlist. I would like to select a value from the dropdownlist and depending on that value pull into the View a form related to that selection.
Looks like this:
I would like the form to appear below this ddlist and if the user changes the value in the ddlist, it would change the form.
Here's my "Add" View:
<div id="matSelContainer">
#Html.Action("SelectMaterial", "Materials", "Materials")
</div>
Here's the "SelectMaterial" View:
#model Procurement.Models.Material.MaterialType
#Html.Label("Select a Material Type: ")
#Html.DropDownListFor(
x => x.MaterialTypeList,
new SelectList(Model.MaterialTypeList, "MaterialTypeId", "Name")
)
Here's my Controller:
public ActionResult Add()
{
return View();
}
public ActionResult SelectMaterial()
{
materialTypes.LoadMaterialTypes();
return PartialView(materialTypes);
}
I would like to have a separate View for each Material Type and just call that View based on the selection in the ddlist.
Can someone show me how to achieve this?
Would I add a separate #Html.Action to the "Add" View and then in the Controller have another action return a PartialView?
But how to connect this with the Onchange event?
Update<<
Here's what is almost working for me:
"SelectMaterial" View:
#model Procurement.Models.Material.MaterialType
#Html.Label("Select a Material Type: ")
#Html.DropDownListFor(
x => x.MaterialTypeList,
new SelectList(Model.MaterialTypeList, "MaterialTypeId", "Name"),
new { #onchange="CallChangefunc(this.value)" })
<script>
function CallChangefunc(val) {
//alert("i am a " + obj.options[obj.selectedIndex].text);
//alert(obj.options[obj.selectedIndex].text);
window.location.href = "/Materials/MyMethod/" + val;
}
</script>
In my Controller I have this ActionResult:
public ActionResult MyMethod(string value)
{
return PartialView();
}
My controller is getting called when I change selection but the value coming in is null. I can see on the browser address bar that the expected selected value is being passed. Why is it null in controller? (I tried adding an [HttpPost] to ActionResult with no luck.)

Pass #Html.DropDownList selection using #Html.ActionLink with ViewModel to Controller

I've been reading through posts for two days regarding this, and still have not figured out the answer. I want to capture the DropDownList selection within my ModelView, pass this to a #Html.ActionLink, which will send it back to a specific Action within the Controller.
My ViewModel:
public class ViewModelShipments
{
public ViewModelShipments()
{
tblShipments = new tblShipments();
}
public tblShipments tblShipments;
public IEnumerable<SelectListItem> ShipmentIDsList;
public string SelectedShipmentID;
}
My Controller:
public ActionResult SelShipment(string SelectedShipmentID)//for ShipmentID change via DropDownList
{
int id = db.tblShipments.Max(p => p.ShipmentID); // find last ShipmentID
if (SelectedShipmentID != null)
{
id = Int32.Parse(SelectedShipmentID);//convert text to int
}
My View:
#Html.DropDownListFor(expression: model=>model.SelectedShipmentID,selectList: Model.ShipmentIDsList) #* render DropDownList object*#
#Model.SelectedShipmentID #* display value of SelectedShipmentID *#
<!-- Upon Click, send selected ID to controller -->
<!-- the ActionLink is working, but the routeValues: always contain NULL -->
#Html.ActionLink(linkText: "Submit", actionName: "SelShipment", controllerName: "Shipment", routeValues: Model.SelectedShipmentID, htmlAttributes: null)
Why does the ActionLink(..., routeValues: Model.SelectedShipmentID,...) always return NULL to the Controller ? The Model.SelectedShipmentID is not updated with the DropDownList selected id. Please help as I'm running out of time on this.
Razor code is parsed on the server before its sent to the view, so the value of your route parameter will be the initial value of SelectedShipmentID. Selecting a value from a dropdownlist does not change the url you have already rendered.
You could use javascript/jquery to handle the dropdownlist's .change() event (or the links .click() event) to update the url, however the better way to handle this is by using a form that makes a GET to your controller method
#model ViewModelShipments
#using (Html.BeginForm("SelShipment", "Shipment", FormMethod.Get))
{
#Html.DropDownListFor(m => m.SelectedShipmentID, Model.ShipmentIDsList, "-Please select-")
<input type="submit" />
}
Note the last parameter of DropDownListFor() add a label option allowing you to post back null but not sure if this is appropriate for you.
Since your binding to a value which is int then both your model property and method parameter should be int? not string. In additiona you should change the logic in the controller so that you are not making unnecessary database calls when a valid value is passed to the method.
public ActionResult SelShipment(int? SelectedShipmentID)
{
if (!SelectedShipmentID.HasValue)
{
// only necessary to call database if SelectedShipmentID is null
SelectedShipmentID = db.tblShipments.Max(p => p.ShipmentID)
}
....
}
Side note: From your view model properties, I assume you wanting to display some data in the view based on the value of the selected ShipmentID. If so you should consider using ajax to post the selected value to a controller method that returns the tblShipments data based on the value, either as a partial view or as json, and update the current page, rather than doing a complete page refresh each time.

open a MVC4 view inside a jquery Dialog

I want to take a view and instead of opening a new page I want to just open that view inside a Jquery dialog. I was just wondering how it's done or if possible.
HomeController.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Jquery_Dialog.Models;
using Kendo.Mvc.Extensions;
using Kendo.Mvc.UI;
namespace Jquery_Dialog.Controllers
{
public class HomeController : Controller
{
private IEnumerable<Product> Products
{
get
{
return new List<Product>
{
new Product {ProductID = 1, Name = "Train", Category = "Toy", Price = 29.99M},
new Product {ProductID = 2, Name = "Truck", Category = "Toy", Price = 19.99M},
new Product {ProductID = 3, Name = "Bread", Category = "Food", Price = 2.49M},
new Product {ProductID = 4, Name = "Cookies", Category = "Food", Price = 2.99M}
};
}
}
public ActionResult Index()
{
IEnumerable<Product> productList = Products;
return View(productList);
}
public ActionResult Details(int id)
{
Product model = Products.Where(p => p.ProductID == id).SingleOrDefault();
return Request.IsAjaxRequest() ? PartialView(model) : PartialView(model);
}
public ActionResult About()
{
ViewBag.Message = "Your app description page.";
return View();
}
public ActionResult Contact()
{
ViewBag.Message = "Your contact page.";
return View();
}
}
}
Index.cshtml
#model IEnumerable<Jquery_Dialog.Models.Product>
<link rel="stylesheet" href="http://code.jquery.com/ui/1.9.1/themes/base/jquery-ui.css " />
<script src="http://code.jquery.com/jquery-1.8.2.js "></script>
<script src="http://code.jquery.com/ui/1.9.1/jquery-ui.js "></script>
<table> #foreach (var item in Model) {
<tr>
<td>
#Html.ActionLink(item.Name, "Details", new { id = item.ProductID }, new { #class = "ajax-details" })
</td>
</tr>
}
</table>
<div id="dialog" title="Title of dialog">
<p>This is the default dialog which is useful for displaying information. The dialog window can be moved, resized and closed with the 'x' icon.</p>
</div>
<script>
$(function () {
$('.ajax-details').on('click', function (e) { // bind to click event
// go get the page using the link's `href`
$.get($(this).prop('href'), function (response) {
$(response).dialog(); // take the response and throw it up in a dialog
// optional: Use jQuery UI's options to specify buttons and other
// settings here as well. It's also probably a good idea to
// bind the close event and $().remove() this element from
// the page on close since the user can click links over and
// over. (prevent DOM overload of hidden elements)
});
e.preventDefault(); // don't let it continue on
});
});
</script>
<script>
$("#dialog").dialog();
</script>
As you can see I have a simple dialog that opens a div but I want to be able to open the details view instead of clicking the ActionLink and going to a different page, I want to be able to click the ActionLink and have it open up in the dialog.
Assuming you make the ActionLink a little more accessible (by using a class name for instance):
#Html.ActionLink(item.Name, "Details", new { id = item.ProductID },
/* htmlAttributes: */ new { #class = "ajax-details" })
You also make a modification to the action so we can fetch partial contents when it's an ajax request:
public ActionResult Details(int id)
{
// this is another way of making sure that AJAX calls get partial content,
// but a normal visit would render the entire page.
return Request.IsAjaxRequest() ? PartialView(model) : View(model);
}
Optional You could also adjust your _ViewStart.cshtml file to do the same if this was common place on the website to render partial views/ajax supplementing:
#{
Layout = IsAjax ? null : "~/Views/Shared/_Layout.cshtml";
}
Now, we wire it up with AJAX. Again, reference the class name we game the link earlier (ajax-details):
$('.ajax-details').on('click',function(e){ // bind to click event
// go get the page using the link's `href`
$.get($(this).prop('href'), function(response){
$(response).dialog(); // take the response and throw it up in a dialog
// optional: Use jQuery UI's options to specify buttons and other
// settings here as well. It's also probably a good idea to
// bind the close event and $().remove() this element from
// the page on close since the user can click links over and
// over. (prevent DOM overload of hidden elements)
});
e.preventDefault(); // don't let it continue on
});
Don't have the opportunity to test it, but should get you in the ball park. if it doesn't get you close enough, let me know and I'll revisit the answer and adjust.

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