On my form with my detailed layout of my database in textboxes i can change my data or add new record.
how can i verify if there was any changes to a record when the form is being closed or when my cancel button is pressed.
i want to create a message box that warns tha there hav been changes made should it be saved yes or no
Im using VB.NET 2008
I know I can exit a program by using the End statement.
But i was wanting to know how to check to see if the data has been changed since it was loaded and bring up a diaglog box up saying the data has been changed or not saved, would you like to save the data before exiting?
I will have a form that will have a yes, no, and cancel buttons.
Im using VB.NET 2008 I know I can exit a program by using the End statement.But i was wanting to know how to check to see if the data has been changed since it was loaded and bring up a diaglog box up saying the data has been changed or not saved, would you like to save the data before exiting?
I will have a form that will have a yes, no, and cancel buttons.
I have a WinForms app with a datagridview and a bindingsource. I want the user to confirm changes before I save them to the database. don't want to pop up the confirmation dialog unless I know the user has made changes. So I need a way to check if changes have been made.
View 2 Replieson my Form I have a DataViewGrid and some textboxes with a save button (they are filled with additional data of the selected row).Save is disabled first, when I change something in the textboxes the save button is enabled.When the user changes a gow in the grid, I want to ask before changing the grid row, if he wants to save (if the button is enabled).I am using RowEnter but this is too late, then the selected row already changed (and my textboxes already got new data)...What event can I use to ask if I should save stuff before the user changes a row?Something like BeforeRowChanging with a chance to cancel changing the row?
View 2 RepliesUsing .Net, I need to generate a response based on only the checkboxes on my form that have had there states changed. So how do I know if the check box has changed from its previous value before submission. I can't use the onchange event because the user may check multiple boxes before submitting.
View 3 RepliesI am trying to check if an image has been changed from a picturebox in a if statement. If I cant check if a image has been changed then can I check if a picturebox been clicked.
View 8 RepliesIs there a way to check if the user has changed the value of a textbox?I try to acces a variable in one of my methods to compare against the value but I can not seem to be able to access it?
View 1 RepliesI have a window which has 8 items in a listview along with 2 radio buttons below the listview. The user is able to select one or more selections in the listview and turn the selection on or off with the radio buttons(live, prior to hitting the submit button), my question is how do I tell which selection was changed? I was going to put the one or more selections into a string/array and use that later for some messages once the user hits the submit button. I can almost think of it but can't quite get there, i'll be using an if/else with the .selected option in listview items but am not sure how to tell if the user, say,goes back and changes the option from On to Off(Off originally)to remove that option from the array.
View 2 RepliesWhen DateTimePicker check state changed,ValueChanged and TextChanged events don't work always.
View 8 RepliesIs there a way to check if the date time picker has been changed? I have a date time picker set to allow a person to put in their date of birth and I have it set to no greater date than 12/1/1992, but I need to check that the user has actually selected a date before the form is submitted. Can it be checked?
View 6 RepliesI have a problem with the Validation of a Integer-Field in my application.Its an Access DB on a Windows Form.I implemented the validation in DataSet.vb using an ErrorProvider on my Form.The field name is FNr and should not accept duplicate numbers.If the field value is changed, a query checks if the number already exists in the Datatable and if so it sets the error on that field.If the user tries to change the field to a number which is a duplicate I want to cancel the input back to the original number. This works but the
Error message is still shown by the ErrorProvider.The code is partially in DataSet.vb and in Form.vb
Public Class Funktionen
Private Sub FunktionenBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FunktionenBindingNavigatorSaveItem.Click
Me.Validate()[code]......
How do I check if the original value of a text box has been modified?
I have a few textbox controls on a form. When form loads; user enters data in these fields but later change his mind and modifies what was entered earlier. I need to know which textbox or txtboxes were modified.
I am currently using DevExpress 11.2 within Visual Studio 2010. Currently I am using two DevExpress.XtraBars.BarEditItem which gives me two check boxes (with a label) in my menu bar (DevExpress.XtraBars.Bar) at the top of my windows form. Right now I have working code so that when one checkbox is clicked it unchecks/checks the other checkbox and executes code specific to that box. This works.
My problem is that the DevExpress.XtraBars.BarEditItem does not have a check changed event. Currently I am using the EditValueChanged event as the checked check box is set to True and the unchecked checkbox is set to false. However the EditValueChanged event isn't called until the checkbox looses focus. This doesn't work for me as I want it instantaneous. I looked into the itemClick and ItemPress events but they don't give me the new editvalue and if someone presses on the caption (rather than the box portion) it still fires. Is there someway to get the event right away??
I am looking in two different older projects (both in Visual Studio 2008 and using DevExpress 9.2 and 10.2) and it looks like it does everything the same way as me yet the EditValueChanged event fires right away without any lose of focus.
So I have got a program with a timer on, a few labels displaying coordinates, and two buttons. Here is my
[code]...
It displays the color of the pixel at the coordinate typed into the text boxes.I have a video of a tennis ball which is bouncing on the spot, and the background in brown, so when the tennis ball comes into view there is a significant color change and i want it to start and stop a timer each time the colour changes significantly.So my question is, how do i get it to check whether the colour chas changed significantly?
I changed my Username on my computer from i.e. "xxxxxx x xxxxx" to "Dennis"
VB 2008 during a compile gave me the following error: Error reading icon 'C:Usersxxxxxx x xxxxxAppDataRoamingMicrosoftVBExpress9.0VSProjectApplication.ico' -- The system cannot find the path specified.
The file "VSProjectApplication.ico" is in 'C:UsersDennisAppDataRoamingMicrosoftVBExpress9.0'
Somewhere in the VB2008 "configuration" files I believe that I need to manually change the old path to the new path.
I found the old path in the ".suo" file. The ".suo" file is not a text file. How can I edit the .suo file, save it so that it will work?
Ok, I have been going around and around with this for hours (Searching, etc). This is what I want to do, I want to load data into a Text Box and if the user changes the text in the Text Box I want to be able to save the new text.
My problem in the TxtBox_TextChanged event the data contained in the txtNarrative Text box is the new data that the user typed in (<>ABCD) but in the btnSubmit_Click event the data contained in txtNarrative is the original value ABCD.
<%@ Page Language="vb" AutoEventWireup="false" CodeBehind="Default.aspx.vb" Inherits="WorkBench_VBNet._Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
[Code]....
'm developing multi user systems where for example I could have a form with a list of users on it. If a user on another system adds a user then I would ideally like for the new user to show up on my list reasonably soon. While that could be done by getting refreshing the list every couple of seconds I would prefer to be able to identify that a change has happened and then be able to decide what to do from there (whether that be actually refresh the list or inform the user that a change has happened and ask them what to do).
The only way that I can think of doing this is to store the information that was originally retrieved and then every x number of seconds requery the database and then compare the two sets of data, if there are differences then raise an event.
I have a form that builds and populates dynamic text boxes from parsing a file. There is a "Last Name" text box that when populated, also labels a tab page with the name. After the form is populated, the user can change data as they desire but I was wondering how to update the tab page text when the user updates the last name text box? All the controls are built in code.
View 5 RepliesI am retrieving data from my database using a TableAdapter. I was wondering if there is some way I can tell (or be informed) that the data has changed and I therefore need to do another Fill? That way I can just Fill on demand rather than every time the user requests to see the information and I am forced to do a Fill before showing the data because I don't know if is current or not. For the record I am using an ODBC connection string to access a Pervasive PSQL database
EDIT I was thinking I could check the last write time of the MKD file to check if this has changed but this doesn't seem to be reliable as it is not written to until the connection is closed. Does anyone know the circumstances when this is written?
A quick question on caching dataset objects. How can I know if the data is changed in Sql when caching data? I don't want to specify time constraints but used a strategy where data is changed in sql and I have to refresh my cache?
View 1 RepliesI am trying to get my grid to refresh automatically when the underlying data is updated in the database. Isn't this supposed to work? Or am I missing something? I created a DataTable within my DataSet. Then I created a new form and added a DataGridView (actually I'm using DevExpress' XtraGrid but am trying to get it to work with just the Microsoft controls). I use the menu in the upper left of the grid to set the grid datasource to the datatable in the project data source. This then automatically adds the dataset, BindingSource, and TableAdapter to the form.
[Code]...
I have been trying to do this for ages and having no joy whatsoever.
I have a ribbon window of the following hierarchy:
MainWindow
MainContent (Tab Control)
TabContainerViewModel
ViewModelBase
View model base has an ObservableCollection of tabs type ViewModelBase. The Tab Control itself is binding fine to these, displaying appropriate view models. I have 2 problems however, I want a "NotepadView" (Of type viewmodelbase) to be replicated numerous times (one view many view models).
At the minute, I have 4 views (NotePadViewModelx where x is 1-4) with corresponding viewmodels, this is because each view had the same text per tab. Now I have individual views per tab.
When I type into tab 1 and switch to tab 2, I lose what I typed in tab one when I click back.
My application is like this : i have to search my data from database with some check box and text box when user select check box specific function go on and then when user enters some range of value in textbox then the result will shown in data grid view after that i can print it by selecting data
my vb.net code is as follow:
Imports System.Data
Imports System.Data.SqlClient
Public Class XtraForm1
[CODE]............
I m also pasting the demo picture.
In vb.net using Data Reader while selecting an value in combobox should display an selected value record from the database into textbox.
View 4 RepliesI want to track changes in an application. So I've made a copy of the main table in that application, and am accessing both tables in the application using two separate datasets.
My plan was to use the HasChanges method of the main DataSet to get changed rows and then insert those into the copy table. When I run the code I get an error:
A first chance exception of type 'System.InvalidCastException' occurred in MyApp.exe
Unable to cast object of type 'MainDataTable' to type 'MainAuditDataTable'.
Here's the code:
If Me.DataSet3.HasChanges Then
' 'look for each row that has changes, not new rows
' 'insert that row into the auditing table
[Code].....
I have a class that contains a collection of another class. See below
Public Class Spot
Private mActive As Boolean
Public Sub New()
[Code]....
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[Code].....
MS has a patch for the OnListChanged event handler issue, even though it seems we have to pay to have access to it. This fix specifically addresses an error message when you press ESC to cancel adding a new row in .NET 2.0: [URL]
FIX: Error message when you try to press ESC to cancel adding a new row to a DataGridView control in the .NET Framework 2.0: "An unhandled exception of type 'System.InvalidOperationException' occurred in System.Windows.Forms.dll"
I have a program for school project that has input fields for Name, Address, City, State and Zip. I need to error check so that the fields are not empty.I have used If statements that check to see if the fields are empty and shows a message box if they are but if I leave the whole form empty and click the button that activates it, all the if statements go- one by one instead of pausing for the user to input the required data.How do I check for data and make the program stay there until the data is input? I have tried TRY/CATCH but it won't catch this type of error.
this is the
'This program computes customer's bills at the pizza shop for all combinations of
'crusts, toppings, sizes and discounts
Option Strict On
Public Class PizzaForm
[code].....
when the user clicks on the add button another form launches, which enables the user to add student info such as name, address, course, start date and end date, this information is then written to class when the ok button on that form is clicked, and then displays the data on the initial form in data grid. the user can add multiple entries and they are all displayed on the intial form and a the data grid is populatedwhen any of the rows in the displayed grid is selected, and the update button is clicked then the same form launches as the previous one and but this time its in the update mode and pre populates the form with the inital values.
View 3 Replies
