I can't provide a project or even code snippets that would make sense out of context because the code base is too complex for an easy replication to be setup.
We are trying various things like calling Refresh, Update.
Hoping this is something you've encountered before and have some suggestions.
C#. net core 6, winforms application, TekerikNuGet3 package source, UI.for.WinForms.AllControls.NetCore package 2022.2.622
I am trying to export selected cells from a RadGridView as a csv file.
When using "var exporter = new ExportToCSV(Dgv)" then "exporter.RunExport(fileName);" writes the csv file correctly. It exports every cell.
It doesn't support exporting selections so I wrote a function to do this . The one below is what I used in my project to test what I was doing. It initially writes the csv to a worksheet and wrote that using formatprovider to file, then I just created a stringbuilder adding quotes and appended that to the file afterwards.
Writing the worksheet, the csv values haven't been quoted, plus number fields have had leading zeros removed which proves to be a problem when telephone numbers are stored in a field.
So I googled and found the Settings property which is there to set csv options. But they are private, not public therefore I can't set up the csv propertly.
private void radButton1_Click(object sender, EventArgs e)
var workbook = new Workbook();
var worksheet = workbook.Worksheets.Add();
var rowIndex = 0;
var columnIndex = -1;
var sb = new StringBuilder();
var prevColumnIndex = -1;
// ForEach cell are accessed vertically then horizontally.
foreach (var cell in Dgv.SelectedCells)
// Cell is included in selection even if it's invisible
// so check visibility and ignore if it isnt
if (!cell.ColumnInfo.IsVisible) continue;
// At bottom of column, rownum will change. Watch for this
// and reset x and y values
var rowNum = cell.RowInfo.Index;
if (rowNum != prevColumnIndex)
prevColumnIndex = rowNum;
rowIndex = 0;
else if (!string.IsNullOrEmpty(sb.ToString()))
var value = cell.Value;
worksheet.Cells[columnIndex, rowIndex++ ].SetValue(value.ToString());
var fileName = @"C:\temp\SampleFile.csv";
IWorkbookFormatProvider formatProvider = new CsvFormatProvider();
using var output = new FileStream(fileName, FileMode.Create);
// Write contents of sb to the file for comparison sake
I just upgraded to the latest version of Telerik products and facing the issues described below.
When dragging and drop Telerik UI objects from the toolbar on a form, the dialog box below is displayed with question but there is no button to click to answer the question and I don't where to stop it.
See screenshot attached.
Dear Ladies and Gentlemen
Currently I am trying in vain to upgrade to the latest version Telerik UI for WinForms 2022.1.118.
However, the update fails with the error given below.
I have already uninstalled and reinstalled VS2019. Unfortunately this did not help.
Can you help?
I am have a problem with pdf wiewer when the PDF file contains an images , it is slow in movement and it is difficult to navigate between pages. Is it possible to fix this problem
Note:- I am using Bound RadTreeview. Bound with DataSource.
1 Take RadTreeview
2 Add Few nodes Like:
3 Now Drag Node B and Drop it in Node C (As Node C's Child)
4 It throw Exception Error Msg "Collection was modified; enumeration operation may not execute."
5 Now Try to Drag Node E and Drop it in Node B, again same error occurs
6 Full error screen i attached here.
Please reply as soon as possible.
I have made User control for custom node, in this user control i have used following controls
1 RadLabel (no of control - 3)
2 RadPanel (no of control -1)
3 PictureBox (no of Control - 4 )
4 TableLayoutPanel (no of control -3)
Means i have used total 11 controls within my user control.
Height of usercontrol = 146
Width of Usercontrol = 595
I have taken RadTreeView and above UserControl added as Node,following properties of treeview is set
this.radTreeView1.DataSource = Staff.GetStaff();
this.radTreeView1.ParentMember = "ParentID";
this.radTreeView1.ChildMember = "ID";
this.radTreeView1.DisplayMember = "Department";
this.radTreeView1.CreateNodeElement += this.OnCreateNodeElement;
this.radTreeView1.TreeViewElement.AutoSizeItems = true;
this.radTreeView1.ShowRootLines = false;
this.radTreeView1.FullRowSelect = false;
this.radTreeView1.ShowLines = true;
this.radTreeView1.LineStyle = TreeLineStyle.Solid;
this.radTreeView1.LineColor = Color.FromArgb(110, 153, 210);
this.radTreeView1.TreeIndent = 50;
But when i run the code it shows like this means my control is not displaying and the property "AutoSizeItems" is not working.
hope for quick reply
Good Evening , As per your suggestions i make my custom treeview node with LiteVisualElements .
In That Node i have taken one StackLayoutElement and RoundRectShape assigned to it but still panel shows corners instead of round edges,
i tried with different properties and styles but not get succeed , so please help me out.
here i have attached image of my node and "stackLayoutElement" code too.spnlControls = new StackLayoutElement();
We have recently found a bug on both the RadDocument and Rad Rich Text Editor. Created a RTF document via the RadRichText Editor. The RTF document contains a table. When the document is saved and loaded from the same form, it is displaying correctly, however when loaded from a different form, it seems to have shrunk and lost the column width, thus having long and skinny columns.
We have set the fixed column width on the table, however this did not seem to solve the issue.
I have attached two screenshots for reference. One with the correct looking table, and one with the long and skinny columns.
Is there a workaround, or is this a known bug?
Long and skinny columns:
Currently on Telerik Winforms version 2018.3.1016.40
I have a form which contains TreeView control. I need to convert it to RadTreeView. So I replaced TreeView control with RadTreeView and TreeNode with RadTreeNode in the code. I found that the events in both are different, so tried to replace the events with similar events in RadTree.
Following are the events that I have replaced in my code :
Private Sub TreeView1_AfterExpand(ByVal sender As Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles tvMain.AfterExpand
Replaced by -
Private Sub TreeView1_AfterExpand(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.RadTreeViewEventArgs) Handles tvMain.NodeExpandedChanged
Private Sub TreeView1_AfterCollapse(ByVal sender As Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles tvMain.AfterCollapse
Replaced by -
Private Sub TreeView1_AfterCollapse(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.RadTreeViewEventArgs) Handles tvMain.NodeExpandedChanged
and included Expanded flag to check if it is expand or collapse.
Here, I noticed unwanted firing of this replaced event when compared to the old event, but I handled it using the Expanded flag.
Private Sub tvMain_AfterSelect(ByVal sender As System.Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles tvMain.AfterSelect
Replaced by -
Private Sub tvMain_AfterSelect(ByVal sender As System.Object, ByVal e As Telerik.WinControls.UI.RadTreeViewEventArgs) Handles tvMain.SelectedNodesChanged
This event gets fired twice while clicking on a node.
My main issues are,
See attached screenshot. The popup calendar looks wrong when running on a display with 250% scaling. Surely, that's not correct. The calendar should not be so large and the fonts so small. Am I missing something? I have done all the other steps to enable High DPI support, and as you can see, the textbox area seems to scale fine.
i am getting a null reference exception with the following call stack:
Description: The process was terminated due to an unhandled exception.
Exception Info: System.NullReferenceException
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=184.108.40.206, Culture=neutral, PublicKeyToken=b77a5c561934e089]].GetScrollHeight(System.__Canon)
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=220.127.116.11, Culture=neutral, PublicKeyToken=b77a5c561934e089]].ScrollDown(Int32)
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=18.104.22.168, Culture=neutral, PublicKeyToken=b77a5c561934e089]].ScrollTo(Int32)
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=22.214.171.124, Culture=neutral, PublicKeyToken=b77a5c561934e089]].scrollbar_ValueChanged(System.Object, System.EventArgs)
at Telerik.WinControls.UI.RadScrollBarElement.OnValueChanged(Int32, Int32)
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=126.96.36.199, Culture=neutral, PublicKeyToken=b77a5c561934e089]].UpdateScrollValue()
at Telerik.WinControls.UI.ItemScroller`1[[System.__Canon, mscorlib, Version=188.8.131.52, Culture=neutral, PublicKeyToken=b77a5c561934e089]].UpdateScrollRange()
at Telerik.WinControls.UI.GridTableElement.UpdateViewCore(System.Object, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.GridTableElement.UpdateView(System.Object, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.GridViewEventProcessEntity.ProcessCollection(Telerik.WinControls.UI.GridViewEvent, Telerik.WinControls.UI.PriorityWeakReferenceList, Telerik.WinControls.UI.GridEventProcessMode)
at Telerik.WinControls.UI.GridViewSynchronizationService.DispatchEvent(Telerik.WinControls.UI.GridViewTemplate, Telerik.WinControls.UI.GridViewEvent, Boolean)
at Telerik.WinControls.UI.GridViewTemplate.DispatchEvent(Telerik.WinControls.UI.GridViewEvent, Boolean)
at Telerik.WinControls.UI.GridViewTemplate.DispatchDataViewChangedEvent(System.Object, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.GridViewTemplate.OnViewChanged(System.Object, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.MasterGridViewTemplate.OnViewChanged(System.Object, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.GridViewTemplate.EndUpdate(Boolean, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Telerik.WinControls.UI.MasterGridViewTemplate.EndUpdate(Boolean, Telerik.WinControls.UI.DataViewChangedEventArgs)
at Communication_Logger.ChannelClass.Serial_DataReceived(System.Object, System.IO.Ports.SerialDataReceivedEventArgs)
at System.IO.Ports.SerialPort.CatchReceivedEvents(System.Object, System.IO.Ports.SerialDataReceivedEventArgs)
at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
the setup is a dotNet 4.5.2 winforms application with RadGridView in virtual mode.
The exception occur when the application is left working for days (2 in this case) without any user interaction.
The application normally updates a list that is used by the gridview, the list records are added and removed continuously, the grid view RowCount is updated via a timer.
i suspect that the RowCount reported at one point in time doesn't match the list size as it is trimmed, and therfore the GetRowHeight fails as the data doesn't exist - can this be handled in the gridview - to avoid a termination of the process due to the exception ?