I have an application built that has several forms. I use an XML file to store settings data (mainly folder names for data output) and I need each form to be able to access and modify the data. I'd also like each form to access functions from a main form (such as file parsing functions). I have read articles about properties and inheritance but I need some guidance as this topic is pretty confusing.
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My question is, am I able to share a business logic layer seemlessly between the two presentation layers or is there anything I need to watch out for. I'd really like to not have any duplication of business logic, so any advice would be more than welcome.
View 3 RepliesI am working with several RFID readers that perform different function in my vb.net program. Currently each reader port number is hard coded into the respective form. For example, reader 3 operates on COM1. However, this will be problematic when installing on different machines.
What I would like to do is have a "configuration" form where the user can select each reader and then select the COM port. Then all other code references these settings. What would be the best approach for this.
The only way I know to do it currently is to place this information in a small database and then have the forms reference that database, but it is a lot to do for such a seemingly trivial task.
I have some icons and images that are stored as embedded resources in my form1.resx file. Is there any way I can access these resources from my Form2 without adding the icons as project resources?
View 5 RepliesHow do I share text between forms?I want a box to popup exactly like a input box, but needs to be multiline, Is there any east way to do this or will I have to create a second form?If so, how do I share the string between forms to then output in a textbox on 1st form?
Also, I have VB 2008 Standard, and I want to build an application for a handheld, Is it possible to build an application and then pass it over to someone who has the professional version to make it work on pocket pc? Or does the entire build have to be on pro already?It's a very simple program...
I am trying to figure out how to seperate my business logic from my forms. This is my first attempt at doing this, but I would like to figure out how to handle events from multiple forms within a class. I have found myself routinely writing the same logic over and over in each form class and its time I figure out how to completly seperate out that logic in winforms so I can reuse the methods across all of my forms.
So basically I have this click event in form1:
Private Sub btnSubmit_Click(sender As System.Object, e As System.EventArgs) Handles btnSubmit.Click
[code].....
When I declare a variable as public, shouldn't it be available in another form? I am trying to write a windows mobile prg with 12 static mileage points, form1 has the 12 buttons for start point, but when I call form2 with the destination points, my start variable value is not carried over. I intend to then assign a mileage based on the two points and write to file on mobile device. We support 12 schools, and I want my employees to track mileage easily.
Public Class main
Public start As String = "start"
Public dest As String = "dest"
Public miles As Decimal = 0
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i've almost completed my Yahtzee game except for the high scores function. I've got everything worked out except how to take the highscore variable from Form1, and share the data with Form 2
View 12 RepliesI need to share variables across two forms in vb.net. One of them is the main form and the other is a child form.
Create a static/shared variable in one of the forms and access it in the other forms via:
Form1 frm = new Form1(); //creating object of parent to access shared variable
frm.a = "abc"; // passing value
Send an instance of the main form to the child form when creating the child form. The variables can then be accessed via a property function. Create global variables in a module. This seems like the easiest option, but I doubt it is the best option.I also read something about delegates and events, but I don't know how to implement this.
What I mean is that when I make queries on a Parent Form. Child forms can also retrieves the datatable /datarows from its parent form.
View 3 RepliesI'm starting to put in a database into my application, however I'm drawing a blank on how to share a database connection among the dozen or so different forms in my MDI application. I'm assuming this has to do with interfaces or something but I can't find any relevant examples anywhere. Can someone help me out? Ideally what I'd like is when the app is loaded up there is a call to a function in the forms loading area which establishes a single connection to the mdb, that I can then call via any form so I don't always have to open/close connections everytime I need to update the db?
Here's a basic example of the mdb database access code I've got working:
Dim dt As DataTable = New DataTable()
Dim OleDbTran As OleDbTransaction = Nothing
Using connJET As OleDbConnection = New OleDbConnection("connection string here...")
[code]....
I have a form that can spawn a child form, something like:[code]I want to be able to launch multiple children. Unfortunately, I seem to be getting conflicts within the controls of the children. One button will run the other child's control, etc. They also seem to think that their class-level variables are accessible to each other. Private Shared variables like the following are conflicting (one form thinks it's seeing the other form's "mp3file" variable as their own):[code]How do I spawn children forms that keep their controls and data separate?
View 1 RepliesI have two forms A and B. B is a child of A - i.e. I have a button on A that pops up form B. I want B to be able to access and change data (e.g. an instance of an object etc.) in A and also to call some function in A. At the same time I'd like to preserve the right to alter the data in A without opening B. I've achieved this using the following (i.e. by declaring the object and method as Friend):
Public Class frmA
Friend _data as Hashtable
Friend Sub GetData()
If _data IsNot Nothing Then
_data As New Hashtable
Is there anything inherently wrong with the what I've done and if so how can I achieve a similar result? (It seems to work - I can read, add to and change the values in the _data Hashtable from within form B and when B is closed the values persist i.e. I can access the changed values from within form A. I just dont know if its a horrible fudge).
I am sharing databinding when opening a detail form a summary form. The data is shared fine. What I don't know is how to save any data that may have changed, or to create a new record.[code]...
View 2 RepliesI have a very simple 2D array, it holds a list of song titles, their genre, and their runtime. frmMain loads the array from a text file and allows me to manipulate it and boil it down to a desired (implicitly sized) playlist. i want to THEN pass that playlist array to a second form, frmPlaylist The problem i'm running into....When frmPLaylist calls the Property from frmMain I receive an error that VB cannot convert the string value to a two dimensional array. Simplified...frmPlaylist is all locked and ready to receive a 2D array, but frmMain seems to only be sending a single string variable. on frmMain
Public ReadOnly Property PlaylistOut() As String
Get
Return mstrTimedPlaylist(,)
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My question is in two parts:
1) I am writing an application for a touchscreen which will have several different Forms - each of which will be full-screen. What is the best way to achieve this? Hide/show each Form as the user navigates between screens? MDI Parent with multiple Child Forms becoming visible 'on top'? Or is there a more elegant solution?
2) I would also like a 'banner' on the top of each Form (or always visible on the top of the MDI Parent, etc) similar to a 'navigation frame' on a website. This banner will display a clock with the current time, and the current GPS location (meaning that a Timer will be used to get/set these values every 1000 milliseconds). I thought of using a UserControl for the banner - but if this is used on multiple Forms then I will end-up with multiple Timers all waiting 1000 milliseconds to update essentially the same information.
Is there a best practice for this type of scenario? - my thoughts so far are using the "Main" Form for Global Timers, etc - but then how do I update all Form clocks each second? (without iterating through all visible Forms... which seems messy).
Am new to VB, can anyone tell me very simple how to share the MAIN Bindingsource with an detail form where i want to edit 1 record from the main datasource?
andreg
I want to add a close button to a custom navigator. That's fine.
Now what if I want to use it on every form that I would create ? What is the best way (Is subclassing possible for this control in that case, ...) ? Any inspiring code somewhere even for another type of control ?
How do design settings forms
View 2 RepliesI'm working in VS 2008, on a windows application.I have many forms, and I'm in the process of redesigning the GUI.Is there anything that I can do to standard some of the placement of the controls. For example, I have a header for each page, at a certain size and location. Instead of going to each form, is there a way to do the settings once, and apply to many forms?
View 2 RepliesI want 2 forms the main form which is form1.vb and the second form which is form2.vb to share the same value:
Dim Name As String="App1" so i can use it by simple doing that:
[Form1.vb]
Public Class Form1
[Code].....
Or it could be better if i didnt have to add a reference to the main form the string Name should be already declared in the second form so i could use just:
Textbox1.Text = Name
I've been trying to get my head round a problem for days now, I want to read 'File.ini' line by line checking if specific text exists in the file and then display on a windows form weather particular settings are turned on or off.
So far this code works if "TargetText" exists but if it doenst I get an error on the code line: "If line.Contains("TargetText") Then".
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It works if "TargetText" existin in a line in the file but if it doesnt exist I get the 'Null Reference Exception. Object reference not set to an instance of an object.' Any suggestions greatfully recieved!
I have set the name of my Form text in the application settings and I need to rewrite it. Is it possible as it is showing me that it is only a readonly.I know that we can simply change it by using me.text="" But I have a problem in my application as I have the below code where On every time the form loads it is erasing the text.
Protected Overrides Sub OnLayout(ByVal e As System.Windows.Forms.LayoutEventArgs)
MyBase.OnLayout(e)
'Me.Text = CStr(Val(Me.Text) + 1)
FillList()
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I created this program to automatically post reviews I have written to this website. All the code works fine until the last line. It throws this error "Object variable or With block variable not set." I can't figure it out, because it works fine before this point when i call it on other pages.
Dim email, password As String
email = "email"
password = "password"
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I am trying to access MS/Word document properties without opening the file in Word. Right now I have an app that reads the document properties but it has to open the document in word. This makes it run very slowly and also makes it susceptible to crashing if the document is corrupted. In Windows Explorer, you can right-click on a word document file and select properties. The ensuing dialog box contains, in addition to the usual information, two additional tabs labelled "Summary" and "Custom" that correspond to the same tabs in the dialog box you can open from File/Properties menu in Word. I know windows explorer is not opening the document in word because there is no instance of word.exe in task manager and because it has no difficulty in obtaining this information from the file even when it cannot be opened in Word because the document has become corrupted.If anyone could help me figure out how to read custom and built-in document fields (properties) from the file without opening it in Word,
View 1 RepliesI have a question how can I save in My.Settings only the font name and not the size.I have a form where I can change the font for a label on another form. This works perfect.I can even save it in my.settings.
The thing is though, that on that other form I have 2 labels, thet should have the same font name, but the size should be different. (label1 has font size = 40 (can be changed) and label2 should have a fixed font size (should not be changed)).I tried to use label2.font.size = "14", but font.size is readonly.
i have a windows form that has a web browser control.
i need to pass the value from the windows form to the html doc.
here is my problem.... can pass the value across to to a function in the html page but when i try to pass the same value to an image tag in the same document it does not read the value.
here is my code from the winform
If e.Url.Equals(wb1.Url) Then
wb1.Document.InvokeScript("fetchImage", New Object() {path})
End If
it passes through the variable 'path' to a function in the html doc.
heres the code for the html doc.... this part of the code works
function fetchImage(path) {
var now = new Date();
var zm_image = new Image();
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In my app I am using a web browser control, I am displaying a list of files that are there in selected Directory, when the file type is of some image I do it as WebBrowser1.Navigate(sFileName), the image is then displayed in the Web Browser Control, when there is Word Doc I had code that converts the word doc to HTML and it is displayed in the WB Control all good so far, now when the file is of type xls, xlsx I am not converting the file to HTML instead I just use the navigate command and open the file in Excel so that user can then edit it and save it on his system. Now the problem is lets say I am toggling through pages in Directory first file is Image so it will be displayed next when it is Excel file then it will open the file in MS Excel but the WebBrowser COntrol has that previously opened image, I want to clear that when the excel file is opened. So here is what I tried. [code]It navigates to Excel file but does not display text and the image from previous file persists in the web browser control.I even tried to navigate it to "about:blank" but it then does not navigate to Excel file.
View 2 RepliesIam using vb.net 2008.I have richtextbox. I save as wordpad format [rtf] file. Now I need to view it in inside the panel of my form.[code..]
View 1 RepliesSharing applicaiton settings across many applications
View 7 Replies