Validating Controls Within (WinForm) After Data Populated
Mar 18, 2011
I have a form with a datarepeater that contains various controls (i.e. datetimepickers, text boxes, combobox) that are populated via a binding source. I also have other controls on the form that are not part of the data repeater. I would like to force validating all controls after the data is populated. I have successfully forced validating the non-datarepeater controls using Me.ValidateChildren() at the end of my load event. However, it does not fire the validating events for the controls within the data repeater. I have unsuccessfully tried many different attempts to set and move focus within the datarepeater controls trying to get the validating events kicked off. I am not sure where would be the best place (e.g. in drawItem? in ItemCloned?) to place the code and what it should be exactly.
Here was my latest attempt:
Private Sub DataRepeater1_DrawItem(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.PowerPacks.DataRepeaterItemEventArgs) _
Handles DataRepeater1.DrawItem
For i = 0 To e.DataRepeaterItem.Controls.Count - 1
e.DataRepeaterItem.Controls.Item(i).Focus()
e.DataRepeaterItem.Controls.Item(0).Focus()
Next
I successfully handled the validating events in the data repeater caused by user input errors. However, I have the unusual situation that the data coming into my form is already bad for some of the controls. The purpose of the form is to validate the data coming in to it and from user-input. I am newbie with vb.net.
When my form loads, before the ComboBox has been populated and selected this Event (SelectedIndexChanged) gets triggered. How can I prevent the code insides this Event from Executing before form has completely loaded? I tried testing for .SelectedIndex but it returns 0.
How to properly create custom controls containing populated lists?For example: I need a combobox control which contains a list of products, then I would reuse this control in other project.
[Code]...
and it works but when I run the project each item is duplicated - this is because list is populated twice. First when user add a control to form, second by designer when project is started.I already found a solution to prevent adding items in edit mode, but this is not what I need. I would like to have them existing in edit mode so they could be edited at this point.
My form contains a datagrid and a checked listbox. The listbox is populated on the form_load event. There's a function called when the datagrid's SelectionChanged event is triggered that modifies the checkmarks in the listbox. It all works fine when I manually click on any item in the datagrid.
However, the very first time the form runs, the checkmarks are not affected, even though the first item in the datagrid appears selected. I discovered that this is because the actual listbox is not yet populated on the form at the time the very first SelectionChanged event is triggered. So when the function tries setting the checkboxes, it doesn't get anywhere, since it doesn't see any items in the listbox.
Somehow the datagrid is getting populated, even before the form_load event is triggered. I need the listbox to be populated before the datagrid is populated, but I have no idea how to control this.
CompatibleTextRendering support for winform controls. label, check box etc have a property UseCompatibleTextRendering when this property set to true your app support East Asian languuages without having installing there languages on windows. But there is no UseCompatibleTextRendering for textbox, listbox, contextmenustrip etc i can Inherits ContextMenuStrip for this support using this code.
Public Class MyMenu Inherits ContextMenuStrip Public Sub New() Renderer = New MyRenderer()
[code]...
if we can add this support to other controls like listbox combobox etc.
In main thread I create panel(s) (based on some configuration), and then in the next step based on the file type (like video, ppt, image...) I create appropriate controls (dynamically) to show on the forms.
The creation of the control will be done in separate threads (for each file). After creating the control, it throws an error when I try to add that control to the panel (which was created in the main thread), something like cross thread violation, control was accessed from one thread other that it was created.
Can some one please help me in this regard? In this scenario, everything - creating the panels and controls - will be dynamic. Nothing will be static.I tried some of the articles found here on StackOverflow (like, control.BeginInvoke() .. etc), but wasn't able to solve my problem.
I've created a news ticker control, which reads from RSS feeds and scrolls the text Horizontally. The plan is to have 3 of these on my Windows form, which will each display their own information.
The control is created as a label, which is populated with the text, and then scrolls right to left using a timer, once the label gets to the end of the text, and disappears of the left side, the rss is re-read, and then the cycle resumes. The problem is that with multiple copies of this controls on my form, once one gets to the end of it's run, all three freeze while the rss is reread, rather than just the control that needs to do it.
Is there a way to run each of these controls independently (threading?)? Or is there a glitch in my code causing this? (below - some elements not included, but it should be fairly obvious what is happening!)
I drew a Group Box around a bunch of controls cause I wanted to the Box, meanwhile all the controls are glued to the Group Box. How can I remove the Group Box without removing the Controls?
I need to get all controls on a form that are of type x, I'm pretty sure I saw that code once in the past that used something like this:
dim ctrls() as Control ctrls = Me.Controls(GetType(TextBox))
I know I can iterate over all controls getting children using a recursive function, but wondering if there is something more easier or straightforward, maybe:
Dim Ctrls = From ctrl In Me.Controls Where ctrl.GetType Is Textbox
I have a winform with a main panel that is anchored top, left; dock: fill, and set to a specific size to contain another panel of content that we want to scroll through. The other panel along with a few other controls are on the main panel. Now, for some reason, after running the application the controls will be shifted down (never horizontally) some random amount. Now, the "random amount" may in fact be the last position of the scroll bar or something, but either way, it is unintended functionality. I have resorted to automatically resetting the locations of these controls on the main form in the constructor?
See our Posting Guidelines for our policy on archived threads.I am confused as to where to place the following code snippet in my code. I put the function above my load event and the same exception still occurs:
An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in system.data.dll
In my program i have a listbox populated with data from a sequential text file. [code] Mary, Murphy, 16, 893782, Douglas etc.From here the user selects the person they wish to see displayed in the datagrid with all all other relevant details from the text file displaying. Problem is I cannot figure out how to refer to the selected person and then get it displaying on its own in the datagrid. [code]
i have a Checkedlistbox in a windows form, and have defined 5 values in it.Also the form holds a datagrid in it. i have manually defined 2 columns in it.Now i would like to populate datagrid with some data according to the check list values selection. When any selection was done in the checkedlistbox, some data need to added to the gird.in case if i am ticking further selection, i need the datagrid to be inserted with additional values with the prior populated data.
being a beginner, i am not able to get any idea to get this worked.
i need help with stream writer, i can get it read lines and stuff like that but now i need Streamwriter to write to a colour.txt file (already populated with data) and insert a line that isn't already in the file, into alph order eg combobox reads and displays list from txt file.
their is a colour thats isn't in the text file, so i would like it to take the colour from the combobox that was typed in by the user and place it into the colour.txt file in alphabetical order (these are car colours so their are 100's and 1000's per manufacturer, its not as basic as i want red blue black lol) i was able to find loads of data about streamreader but not so much about stream writer
I am trying to see if producttextbox.text (getting ready to be entered) is duplicated in the DB. I have searched and search and typed some code but nothing is working. Code shown is so far the closest.I do get the NO MATCH message box now although it is a duplicate record. At least I know I am getting somewhere...
Public Sub ValME() Dim dv As New DataView(FSC_DATADataSet.PERS) dv.RowFilter.Contains(ProductTextBox.Text)
After I have retrieved my data from my access database, I would like to insert text into one of the columns in a new row. Is this possible? Here's a snipit of my code I use to retrieve the data from access:
If con.State = ConnectionState.Closed Then con.Open() sdr = cmd.ExecuteReader() rtime = Now()
[Code]....
It's the rtotal_time value that I need to insert into a new row, in and cell, the datagrid.
For example, is this an acceptable way of checking that fields are not empty before submitting data to a datatable/database? Right now, Im simply checking with an If statement, and I'm starting to think that this is not the correct way to do it.
I'm also trying to learn more about unit testing, so if you have any tips or tricks, please feel free to share.
So I'm developing a Windows Forms Application in Visual Basic 2010. The user searches for data and fetches results, updates fields and some other CRUD operations. I want to provide a user input validation. Usual stuff i.e. some fields need to be always numbers>0, others need to be non-empty in order to avoid Null access on some objects and others just need to be some fixed strings.
I am writing below code for validating compulsary field account no. in form.User's requirement is set focus back on field when error comes :
If txtAccountNo = "" Then MessageBox.Show("Account no filed can't be left empty") txtAccountNo.SetFocus Exit Sub End If
It's working properly. But suppose user don't want to fill form and exiting from application.Message box keep on appearing till user enters account no.
Does anyone out there have any experience programatically retreiving the lat/long from a GPS attached to a mobile PC?team I'm on is currently looking at hardware options--as the programmer who will eventually have to live with whatever is selected I was wondering if anyone out there has had experience writing .Net programs that interface with a GPS?
Visual Studio 2008 service pack 1 comes with Visual Basic Powerpack and has DataRepeatr control. i want to know that how I can add data in this control. i have in memory data. the examples i found on net are about binding DataSet to DataRepeater by fetching data from database. i want to bind in memory data. how to do this.
I have two VB projects in one VS2010 solution. The first program brings in about 60 integers every few seconds from my PC's serial port. The second program, published via Click-Once and running on my customer's PC, needs to see that new data every two to five seconds.
Is there a simple and reliable way to accomplish this, staying with VB? WCF is way over my head.
I have two VB projects in one VS2010 solution. The first program brings in about 60 integers every few seconds from my PC's serial port. The second program, published via Click-Once and running on my customer's PC, needs to see that new data every two to five seconds.
Is there a simple and reliable way to accomplish this, staying with VB?
I am using VB.net to create a simple winform. I have the option to save the data I input on that form. I am trying to prevent the user not to save the data if textbox10 is empty. I tried the 'while' loop but I go into an infinite loop. The code is below. The 'if' statement gives the error but allows the user to save.
While Len(Me.techniciansTextBox.Text) = 0 MessageBox.Show("Please Enter a Technician To continue") End While
A Form is to Accept User Name and Password from user, after verification the form should display another form that will accept user's full data. When a user press the Ok button, the information entered on this form should be display in another form (Showing the user what he/she has entered)
i have Design the Firs Form and the second form, how can i pass the information entered on the second form to third, and also what will the code look like I need help on this or Code Sample?
NB: i am trying create an instance of the second form in the third form and declare a variable in the third form that will holed the value, but still not working I want to learn .NET Programming in VC#, ASP.NET And VB.NET. I am student and really get excited when it comes to programming
