I'm using FileSystemWatcher in an application.it monitors the files in a folder, then do some processing. I monitor FileCreate, Change, Rename, Delete event.the problem is: when I copy some images to that folder, it fired the create event, but the file is not actually ready, so, when I load the file in the event handler, it failed.how can deal with this correctly?
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I am working with database information,and I have to add code in a dateforms , load event handler .That should set the value of the date time picker to match that of the date time picker in the main form?
View 1 RepliesI have a form that is built and loaded dynamically when File/open is selected.however I now want to use the same code to open a default file and populate the form using the Form load event to call:
Private Sub OpenToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenToolStripMenuItem.Click how would I do this? Just incase this doesn't make sense, I want the same code to run during form load as if the user selected file/open but do not know the syntax of how to call OpenToolStripMenuItem_Click() from form load.
I have a windows application that has a tab control with 5 different tabs. Each of these tabs has a datagrid view that is populated with data on form load with data from SQL Server. I have an event handler for the datagrids for CellValueChanged that appends an asterisk, "*" to the tab, when a change is made, this is meant to mimic the same behavior in VS or SSMS. The issue that I have just realized is that on page load as the datagrids are populated this event handler is raised thousand of times. I have included an If Then statement to exit the sub if it occurs during page load, but am concerned about the performance implications, if any. Is there a better way to handle such functionality? Possibly a way to ignore the event handler on form load? If not is there a negative impact leaving this functionality in?
View 7 RepliesThe event handlers in my parent class are never called though the events are raised in the child class.
The Code:
Public Class childForm
Public Event checkboxchangedEvent(ByVal checkbox1 As Boolean, ByVal checkbox2 As Boolean)
Private Sub checkboxchanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged, CheckBox2.CheckedChanged
[code]....
I've been fiddling with this for ages and can't get it right. If you have this in C#:
videoSource1.NewFrame +=new NewFrameEventHandler(videoSource1_NewFrame);
void videoSource1_NewFrame(object sender, NewFrameEventArgs eventArgs)
{
// stuff to do in here
}
How would write it in VB? My head is spinning with AddHandler and AddressOf and I can't seem to get it right.
I have a Timers.Timer called COMTimeout, to which I add an event handler using:
AddHandler COMTimeout.Elapsed, AddressOf TimeoutEvent
however, the handler may also be:
AddHandler COMTimeout.Elapsed, AddressOf SecondTimeoutEvent
I now need to remove the handler, is there a way to do it without knowing the name or do I need to keep track of which handler as been assigned?
How do I get a Event Handler to fire from within a nother Event Handler?
View 6 RepliesI have to create controls for inputting info to create people objects in the program, because I don't know how many people they are going to input, I have a button that they can press to add more fields.
I need to add a doubleclick event for these dynamic controls (text boxes), how can I create an event for them if they haven't been created yet. Also, as far as I know you cant make a variable part of an object name while declaring it. I need to do something like
Dim dynamicText & (Append variable counter each time a box is made)As New TextBox
dynamicText &variable counter. Name = "TimeTextBox"
dynamicText.Text = "SdgsdG"
dynamicText.Location = New System.Drawing.Point(100, 100)
[code].....
Also is there a way to like copy and paste a group of controls via code instead of having to code each individual one like if I had to do a text box along with a combo box and a lable all at once, can I throw it into something so I only have to recreate the container?
I am playing around with Drag and Drop, and I am having an issue with AddHandler. I am creating labels and displaying them on a form. Before I add each label to the form, I add 2 event handlers (DragEnter and DragLeave). When I run the code, it hits the first event handler (DragEnter), but doesn't hit the second event handler (DragLeave). Either I have coded something wrong, or the second handler is not being added.
Here is my code (note this is just something Im playing around with for learning):
Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
[Code]....
I'm new to VB and trying to add a Key(Down? Press?) Handler to a dynamicly created textbox. The error I get is "'KeyDown' is not an event of 'Object'". How do I fix this?Here are the relevant parts of my
Public Class main
Structure square
Dim box As TextBox
Dim guessedVal As Integer
Dim correctVal As Integer
[Code]...
I have many textbox controls and they are named as txt1.text, txt2.text, txt4.txt etc.I want to raise the event "Leave" when txt1.text leaves or txt2.text leaves.but with a single handler.
View 2 RepliesI'm working on a program with a fairly complex graphical interface. Due to the volume of information possible in the interface, the tooltip, or something like it, seems likely to be a fairly critical means of obtaining feedback. However, after a bit of testing, there are a few features that I am not really enamored with. First, I am changing the tooltip text dynamically based on the portion of a control that the mouse hovers over. This is done in the Hover event handler. What I am seeing is that once the hover event is raised once for a control, it appears not to be raised for that control again unless the mouse leaves the control and re-enters. Therefore, the tooltip is set based on where the mouse hovers the first time it hovers on the control, then doesn't change until the mouse has left the control.
More disturbingly, the tooltip sometimes doesn't show up at all. It appears that if I am quick enough about moving the mouse over the control, then hovering does nothing and no tooltip shows up at all. The way to get the tooltip to show up is to move the mouse smoothly, and somewhat slowly, over the control, then pause. As long as the motion is slow enough, the tooltip always shows up. However, if the mouse is then moved, the tooltip goes away, and won't return until the mouse has left the control and come back to it. So basically, First, I will look into showing something on MouseMove rather than Hover, as Hover appears to be inconsistent, at best. Yet that doesn't solve the problem that the tooltip is too inconsistent in behavior. Is there an alternative, or timing property settings for the tooltip that improves responsiveness?
remove an event handler from within the event handler?
I have a class that gets data from a hand scanner. When the scan is complete and the data is validated, the class fires a custom "ScanComplete" event and returns the data in a custom EventArgs.
In the calling program, I'm creating an instance of the scanning class and adding a handler for the "ScanComplete" event. In the event handler I get the data that was scanned and then remove the handler.
It seems to be working but it feels wrong to remove the handler while I'm running inside the handler. Will this cause a problem?
When I double click on a form control while in the design view in a Web Application project within Visual Studio 2010, say a 'button' or a 'submit' for example, it inserts a javascript function into my .aspx file. When I do this at work it automatically creates an event handler for the control in the code-behind.How do I change this to that setting?I don't want to type those event handler subroutines every time!
View 1 RepliesI'm working on a Windows Service that watches a few folders for changes, creations, and deletions. It all works well with the exception of one watcher that watches a single file (XML File with Configuration Settings) for minor changes.
I tried taking the Windows Service code and putting it into a simple windows application with start/stop buttons for the filesystem watchers and stepped through it. It never detects the file change of the XML config file. The changes are indeed occurring and the "Date Modified" of the file is updating.
XmlEventReferences = New System.IO.FileSystemWatcher()
XmlEventReferences.Path = "C:XmlReferences"
XmlEventReferences.Filter = "*.xml"
[Code].....
In a windows form application I have:
Private Sub ReadData(ByVal CodeId as String)'...reads SQL Table End Sub
Private Sub FileSystemWatcher_Created(ByVal Sender as Object, ByVal e as System.IO.FileSystemEventArgs)
'do some stuff 'Need CallBack to ReadData
The title pretty much precisely asks the question, but I shall repeat;
When I double click on a form control while in the design view in a Web Application project within Visual Studio 2010, say a 'button' or a 'submit' for example, it inserts a javascript function into my .aspx file. When I do this at work it automatically creates an event handler for the control in the code-behind.How do I change this to that setting? I have used '/resetsettings' already, and other answers to similar questions do not solve my problem. I have reinstalled, gone through every menu I can find (though I may have missed something)I don't want to type those event handler subroutines every time!
I'm trying to complete this airline reservation application, but having a problem in this part of the question:Creat an event handler for the FlightBindingSource's PositionChanged event: select FlightBindingSource in the class Name combobox then select position changed in method name combobox to creat the FlightBindingSource's PositionChanged event handler. Write a code to access the currently displayed flight object and pass its flightNumber to method DisplayPassengers as a decimal.This Is my code so far:
HTML
Public Class AirlineReservationForm
Private database As New ReservationsDataClassesDataContext()
Private Sub FillAll()[code].....
Below I create an array of labels. I would like to add an click event to my labels. Can someone point me in a direction?
[Code]...
When I utilize AddHandler in VB to add my own method to the Click event :
AddHandler Button.Click, AddressOf myButton_Click
I see that my code executes last - after other event handlers for the Button_Click event. Is there a way to insert my event handler in front of other events so that it executes first?
so I have the following
Try
Dim username as String = My.Application.CommandLineArgs(0)
Dim password as String = My.Application.CommandLineArgs(1)
Catch
Msgbox("Cannot launch")
Application.Exit
Exit Sub
End Try
I placed this in the form's load event. What I want is for this check to run before the form even loads.If an error occurs, the msgbox comes up and the form is never seen. When I try the code now, the form comes up the msgbox shows. When the user clicks OK the form closes. I tried placing it in the form's designer but the designer tries loading the form any way. How do I get this check to run before the form shows?
I am making the Transition to VB.Net (using VB.NET 2010 express) and I have a simple problem that is driving me crazy. I wish for my Form when it Loads, initialise and then call a sub and do some stuff eg perform a plot. If i place a button on the form and click it the sub works fine.This task was simple to do in VB6 but for the life of me I cannot get it to work in VB.NET. Has the Form-Load event changed in some way with .Net?
View 4 RepliesI have a calculation project with 6 forms. The last form shows all the input and output data from the previous forms. This is accomplished in form6 load event. Form6 contains about 40 controls (mostly textboxes, labels and few pictureboxes), populated in this way:Textbox1.Text = Form2.Textbox3.Text, etc.I am not sure if this is a good practice. I know I can use the DGV, but it does not suit me because of the graphical reasons.
View 1 Repliesim having a problem i have a startup form now when it load its check the date and check the date that comes from the database now i got i want after the first try now when i try to log out (after log out click the startup form show) and the code does not execute in the startup_load event i use me.hide to close my startup form after login.. is this the problem thats why after 2nd try it does not execute my startup_load event how can i resolve that i use me.dispose but it close all my program..
View 4 RepliesI have a project which has a couple of tabs on form, an usercontrol is on the 2nd tab, when the form loads, i want the load event method of the usercontrol to fire, and the message box should pop up.Please see the attach file, the message box only pop up after the form is loaded and the 2nd tab is clicked, not when just the parent form is loaded.
View 5 RepliesI am using VB.NET for Windows applications. What is the difference between Load event,Activate event and Enter event in the Form and in which order the above event is executed.
View 2 RepliesIs it possible to determine using VB.NET whether a certain event has any handlers attached to it? I don't own the event, in this particular case I want to know which of the items in a Windows.Forms.MenuStrip have their ToolstripMenuItem.Click event handled.
View 1 RepliesAll the code i found for multi-threading is complex and not clear.What i want to do is creating a thread for reading and analyzing a big text file on Form_Load event, so that the form UI building continue without waiting for reading and analyzing the file finish.
View 2 Repliesi am wanting to add handler for controls i add at Page_load at page load i added several image buttons and applied the image urls using -i used the borderwidth propertiy for padding as was having trouble getting a cssclass to work. [code] what i want these Image button to do is when clicked a larger image in another panel will appear so i will need to assign the clicked buttons image url to the large image controls, image url
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