Develop Reference

WPF - Removing hidden unicode characters from pasted string

When copy-pasting an IP address from a share-point site, I can see that the actual value that gets pasted in the text-box is: 123.123.123.123​U+200B, which then returns false when attempting to IPAddress.TryParse(...).
I'm rather new in WPF world, and with the help of some SO posts I have so far managed to resolve this by having the PasteHandler in my code-behind class:
private static void TextPasteHandler(object sender, DataObjectPastingEventArgs e)
{
if (!e.DataObject.GetDataPresent(typeof(string))) return;
var pastedText = e.SourceDataObject.GetData(DataFormats.UnicodeText) as string;
DataObject dObj = new DataObject();
dObj.SetData(DataFormats.Text, Regex.Replace(pastedText, #"[^\u0020-\u007E]", string.Empty));
e.DataObject = dObj;
}
However, I was wondering if there's a more standard WPF way to handle cases like this?

How can I get the value of the autocompleteTextView on button click?

I would like some help. I have this code:
string hozzaadnivalo;
public override Java.Lang.Object InstantiateItem(ViewGroup container, int position)
{
View view = LayoutInflater.From(container.Context).Inflate(Resource.Layout.pager_item, container, false);
container.AddView(view);
Button hozzaadas = view.FindViewById<Button>(Resource.Id.hozzaad);
var autoCompleteOptions = new string[] { "Sajt", "Tej", "Kecske", "Barátnő", "piros", "alma" };
ArrayAdapter autoCompleteAdapter = new ArrayAdapter(container.Context, Android.Resource.Layout.SimpleDropDownItem1Line, autoCompleteOptions);
AutoCompleteTextView mautoCompleteTextView = view.FindViewById<AutoCompleteTextView>(Resource.Id.autoCompleteTextView1);
mautoCompleteTextView.Adapter = autoCompleteAdapter;
hozzaadas.Click += hozaadasListViewhez;
hozzaadnivalo = mautoCompleteTextView.Text;
}
private void hozaadasListViewhez(object sender, EventArgs e)
{
adapter.Add(mautoCompleteTextView.Text);
adapter.NotifyDataSetChanged();
}
So i want to add the text of the autocompleteTextView to my listview adapter, but i cant do it there because it does not exist there. So I made a string that I makde equal to the mautoCompleteTextView.Text, but it will be empty, because it will run at the program start, when the user havent done anything. So my problem is that i cant get the mautoCompleteTextView.Text when the user has pressed the button. If anyone could halp that would be great thanks.

You are declaring mautoCompleteTextView inside your method, so it is only available locally within that method.
If you move the declaration outside of the method, then mautoCompleteTextView will be available throughout the entire class.
// declare it here
AutoCompleteTextView mautoCompleteTextView;
// then instantiate it within the method
public override Java.Lang.Object InstantiateItem(ViewGroup container, int position)
{
... // code omitted
mautoCompleteTextView = view.FindViewById<AutoCompleteTextView>(Resource.Id.autoCompleteTextView1);
... // code omitted
}

Property or indexer '' cannot be assigned to -- it is read only

I have a class that is a list of class objects.
[Serializable]
public class UserRequestOrders
{
private List<RTORequestOrder> m_thisUsersOrders = new List<RTORequestOrder>();
public List<RTORequestOrder> RequestOrders
{
get { return m_thisUsersOrders; }
set { m_thisUsersOrders = value; }
}
}
When I create an instance of this object I need to populate the list variable When m_thisUsersOrders with an existing list of requests (from a viewstate).
MyOrders.RequestOrders = (List<RTODataEntryObjects.RTORequestOrder>)ViewState["vsMyOrders"];
When the page posts back, I cast the viewstate into a list of RTORequestOrder objects, and try to set the RequestOrders property, I get the message that the property or indexer cannot be assigned to. I have a "SET" accessor for the property.
All posts that I have read on this topic state that I need to modify scope in the application settings, but I am not sure how that applies here. I don't have any application settings set.
I am hoping someone can help me understand how I can populate the list from an existing list.
EDIT: Nico, Thanks for your response! Below is the full code from the code behind page. "MyOrders" and "lst" are essentially the same thing. When I am working with "lst" everything works the way that I want it to. The reason that I want to use the "MyOrders" object instead is because I have a method that returns the list as a datatable with only the fields I need to display. (I didnt' show that code because the issue appears to be with the "SET" accessor.) "lst" has the same signiture as the "MyOrders.RequestOrders". Why can I cast the the viewstate into the lst object, but not the MyOrders object?
EDIT: Grant, thanks for your response as well. I don't know how to set breakpoints for ASP pages... :(
public partial class Default3 : System.Web.UI.Page
{
RTODataEntryObjects.UserRequestOrders MyOrders = new RTODataEntryObjects.UserRequestOrders();
List<RTODataEntryObjects.RTORequestOrder> lst = new List<RTODataEntryObjects.RTORequestOrder>();
void Page_PreRender(object sender, EventArgs e)
{
if (ViewState["vsMyOrders"] == null)
{
NewDataGrid.DataSource = (RTODataEntryObjects.UserRequestOrders)ViewState["vsMyOrders"]; // code to show the data in the grid when page loading
}
}
protected void Page_Load(object sender, EventArgs e)
{
NewDataGrid.EnableViewState = true;
NewDataGrid.DataSource = (RTODataEntryObjects.UserRequestOrders)ViewState["vsMyOrders"];
NewDataGrid.DataBind();
}
public void btnSubmit(object sender, EventArgs e)
{
int id = Int32.Parse(TextBox1.Text); // dynamically getting the data from the frontend.
string name = TextBox2.Text; // dynamically getting the data from the frontend.
if (ViewState["vsMyOrders"] != null) // if the view state is already having data then can update the list and assign again to the viewstate later.
{
lst = (List<RTODataEntryObjects.RTORequestOrder>)ViewState["vsMyOrders"];
MyOrders.RequestOrders = (List<RTODataEntryObjects.RTORequestOrder>)ViewState["vsMyOrders"];
}
RTODataEntryObjects.RTORequestOrder thisOrder = new RTODataEntryObjects.RTORequestOrder(id, name, User.Identity.Name, System.Environment.MachineName);
lst.Add(thisOrder); //
MyOrders.AddNew(thisOrder);
ViewState["vsMyOrders"] = MyOrders;
NewDataGrid.DataSource = (IList<RTODataEntryObjects.RTORequestOrder>)ViewState["vsMyOrders"];
NewDataGrid.DataBind();
}
}

Programmatically adding two buttons to each row as it loads

I've created a ListView in a new WPF window and also a function that populates the ListView when it is called. This function just takes the URL of my web server where I've stored the data, increments the "id" and gets the data and stores it in the ListView. Therefore it populates the ListView with a certain number of items.
The problem I'm facing is that I want to add two buttons, ON & OFF, to each ListView item as it gets populated programmatically. i.e, if 16 items are added, I want 2 buttons for each item, and if it's 12 items, the similar procedure. Here's my code:
namespace user_login
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
Window1 W = new Window1();
public MainWindow()
{
InitializeComponent();
}
public void populate()
{
int i;
int num = 16;
for (i = 1; i <= num; i++)
{
string val = Convert.ToString(i);
string currentUrl = "http://xpleria.com/devices.php?query=dev&id=";
string newUrlWithChangedSort = ReplaceQueryStringParam(currentUrl, "id", val);
string result = getcontent(newUrlWithChangedSort);
W.list1.Items.Add(result);
}
}
public string getcontent(string URL)
{
string content = "";
// Get HTML data
WebClient client = new WebClient();
try
{
content = client.DownloadString(URL);
}
catch (Exception)
{
System.Windows.Forms.MessageBox.Show("No Connection detected!!!");
}
return content;
}
public static string ReplaceQueryStringParam(string currentPageUrl, string paramToReplace, string newValue)
{
string urlWithoutQuery = currentPageUrl.IndexOf('?') >= 0
? currentPageUrl.Substring(0, currentPageUrl.IndexOf('?'))
: currentPageUrl;
string queryString = currentPageUrl.IndexOf('?') >= 0
? currentPageUrl.Substring(currentPageUrl.IndexOf('?'))
: null;
var queryParamList = queryString != null
? HttpUtility.ParseQueryString(queryString)
: HttpUtility.ParseQueryString(string.Empty);
if (queryParamList[paramToReplace] != null)
{
queryParamList[paramToReplace] = newValue;
}
else
{
queryParamList.Add(paramToReplace, newValue);
}
return String.Format("{0}?{1}", urlWithoutQuery, queryParamList);
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
string user = textbox1.Text;
string password = textbox2.Password;
string currentUrl = "http://xpleria.com/login.php?query=login&user=wcam&pass=wireless";
string newUrlWithChangedSort = ReplaceQueryStringParam(currentUrl, "user", user);
string newUrl = newUrlWithChangedSort;
string FinalUrl = ReplaceQueryStringParam(newUrl, "pass", password);
string result= getcontent(FinalUrl);
string value = result.Substring(0, 8);
string invalid = "xpleria0";
string valid = "xpleria1";
if (value.Equals(invalid))
{
System.Windows.MessageBox.Show("The Username and/or Password you have entered is invalid, please try again");
}
else if (value.Equals(valid))
{
string sessionID = result.Substring(8, 32);
System.Windows.MessageBox.Show("HI, WELCOME CLETA");
this.Close();
using (new user_login.loading.PleaseWait(this.Location))
{
W.Show();
populate();
}
}
}
public System.Drawing.Point Location { get; set; }
}
}

I'm going to recommend you take a step back and start giving some serious consideration to organizing your code. I realize this isn't an answer to the question you asked but it is the answer to the question you should be asking.
First of all, all code relating to the retrieval of these items from the URL should be moved into a class of some kind. This class should accept the URL string as a constructor parameter and gather all the appropriate data. You should then create another class which you will use to populate with the data for each individual item and then expose this list. By the time you're done the code in your window should little more complex than:
var ItemsGetter = new ItemsGetter(URL);
foreach(var Item in ItemsGetter.Items)
{
// Populate the ListView
}
Once you're done with that I recommend you create a UserControl. User controls are extremely useful in situations where you need to represent a dynamic number of data entities each with their own set of controls which allow operations to be performed on each one. You should create a UserControl with a label and the two buttons you need. The UserControl's constructor should expect a parameter of the data type you created to represent each one of your classes. From there you can have the buttons operate on the data type as necessary.
Finally, you'll probably need a way to have the UserControl interact with the Window. Say for example one of your buttons is "Delete". You'd probably want the item to disappear from the list once the operation is complete. Don't be tempted to tie in your control with the Window by passing it as a parameter or something. Instead, read up on Action events and learn how you can create an event on the user control which you bind in the foreach loop of the Window when you're populating the list view. When the UserControl has completed the delete operation triggered by the button you can raise the UserControl's event which will prompt the Window to remove the control from the List View.
Last but not least, NAME YOUR CONTROLS.
Hopefully this helps.

How to hold a table of data for user edition (before saving in the the database)?

I've been using this programming style, that I've seen in an example and just started using it, because it does the job... I would like to know other programmers' opinion about it...
So the situation is when you have a GridView, or a control based on it like the RadGrid, and you want to keep track of a data table while you are adding, editing, reordering and deleting rows.
Using the session to hold the data table (or list of data) may not be the best solution, because the user may open two identical web pages… Using the ViewState to hold the data may be and option... I have been using an approach like the following:
public partial class DefaultPage : System.Web.UI.Page
{
protected DataLine DefaultDataLine()
{
DataLine dl = new DataLine();
dl = new DataLine();
dl.Number = 0;
dl.Title = "";
dl.Text = "";
return dl;
}
protected class DataLine
{
public int Number { get; set; }
public string Title { get; set; }
public string Text { get; set; }
}
protected static List<DataLine> tempLines;
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
tempLines = RadGridBindStartUpData();
}
}
protected void RadGrid1_NeedDataSource(object source, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
{
RadGrid1.DataSource = tempLines;
}
protected void RadGrid1_InsertCommand(object source, Telerik.Web.UI.GridCommandEventArgs e)
{
GridEditableItem editedItem = e.Item as GridEditableItem;
List<DataLine> table = tempLines;
DataLine newRow = new DataLine ();
RadTextBox rtb;
rtb = (RadTextBox)editedItem.FindControl("RadTextBoxTitle");
newRow.Title = rtb.Text;
rtb = (RadTextBox)editedItem.FindControl("RadTextBoxDescription");
newRow.Description = rtb.Text;
RadNumericTextBox number = (RadNumericTextBox)editedItem.FindControl("RadNumericTextBoxNumber");
newRow.Number = number.Value.HasValue ? Convert.ToInt32(number.Value.Value) : 0;
table.Add(newRow);
}
// ...
So using a static List variable, of a custom object (class), declared in the code-behind of the Aspx page, and updating it whenever the data is edited.
What are your thoughts about this approach? Is it okay? How do you hold your table-format data for edition (prior to saving it in the database)?

Not exactly sure what you're going for, but using a static variable is probably not what you want to do. Static properties are shared across all user/threads, so all concurrent users would be editing the same data.
If you are just looking to persist a small data set across post-backs to the same page, use the ViewState instead. Just be mindful of potential performance issues if you plan on cramming lots of data into it.

It depends on what you're wanting to achieve
Viewstate will keep the data on that page - it won't be available on any other pages (or tabs, or windows)
Session will keep the data on the server, this means it will be available for any page the user is looking at (on your site) and it will keep it until the session times out.
Theres a lot of advtanges/disadvantages to either method, therefore you need to research your situation, here is a start.

You mentioned storing in the session, and how this could cause issues if the user opens up multiple copies of the page, etc...
We had a similar issue so I made a property in code behind on the page and on first page load (if not postback blah blah) I generate a new guid. Then I use the guid value as my session key and I know it'll be unique per page.
You could make a spify property like this...
Public ReadOnly Property SessionDataKey() As String
Get
If ViewState("SessionDataKey") Is Nothing Then
ViewState("SessionDataKey") = Guid.NewGuid()
End If
Return ViewState("SessionDataKey").ToString()
End Get
End Property
But in short, I just use the session.

Thank you very much for your replies! With your help, and some research, I see that both approaches, storing in session or using the static variable are indeed wrong, at least for the purpose I was using them... All your answers were helpful, and although I can only mark one as correct, I would like to leave my appreciation.
Well, for anyone stumbling across the same problem, here’s what I’ve implemented in my pages:
public partial class ScriptAdd : System.Web.UI.Page
{
private List<MyItem> tempMyItems
{
get
{
//if (ViewState["tempMyItemsList"] == null)
// ViewState["tempMyItemsList"] = new List<MyItem>();
return (List<MyItem>)ViewState["tempMyItemsList"];
}
set
{
ViewState.Add("tempMyItemsList", value);
}
}
protected void Page_Load(object sender, EventArgs e)
{
// ...
}
}
And then use it whenever I want to add / insert / update lines to my temporary list:
List<MyItem> table = tempMyItems;
table.RemoveAt(idx);
MyItem newRow = new MyItem ();
// ...
table.Insert(idx, newRow);
Finally, if intended, I store all the items in the database.