I'm creating a calculator in visual basic 2008, and with this calculator I want to implement a feature that can store numerical values in a variable for instance x. Similar to the feature used in most graphing calculator that have the button showing: "STO->". I was thinking on using the My.Settings. But I'm having trouble on it.
View 2 RepliesI am checking for empty string values, but how do i see for the Quantity text box if the user chose only numerical values after the empty string. For example...
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I have a database in my app which loads and displays some information on a form by binding the Comboboxes and Textboxes. However, I need to get some of the other values from the database for calculations before they are displayed on the form and I can't seem to find out how to do this.I could bind a couple of Textboxes to the database and then use those values to calculate, but it doesn't seem like a very efficient way of doing things.The dataset is created using the wizard and the controls are linked in the UI.
Please bear with me, I'm still a noob.
I would I have a program that I use in the computer in my network, but for every user I need to edit the source to this user, thus the user cannot edit his information, just use the program how it was ... So, looking over the internet I found a "program" that may contains my solution... Its a Keylloger, I'm not meaning use this keylogger, no, but it has a a very interest feature: I use the main form to edit the information then after all it create a new program with the new information inside... I use my main program to create every userprofile then my program create a new program with the profile inside...
View 12 RepliesI have several threads all relating to this same subject but I have yet got a answer which I could work with. I think most of that is because of my explaining..So..[code]...
View 3 RepliesFor the code below I get an error for the 1 to 5 part. It says end of statement expected. Is the way i've set out the syntax wrong, e.g the 1 to 5? [code] Also other than storing text to a rich text box what else can store numerical data in multiple lines?
View 6 RepliesI am writing a VB.NET Windows Application which takes numeric user-input and performs a complicated calculation, yielding many numeric output variables. Previously, I wrote a similar program in VB6, which output the results to a rich text box using fixed-width font in order to organize data in columns and used asterisks to delineate table areas and section borders. I then used the printer object for printing the output. This method was very archaic and difficult to modify when changes were necessary.
View 5 Replies1. Is it possible to store images in the variables or something like that, then store the images of things that are not buttons, picture boxes or panels?
2. What is the fastest way to store images in Visual Basic?
3. Is it possible to create a list of the class Bitmap and post a picture in each bitmap in a forloop? If it works I would like to see some examplecode.
Which is the best way to store global variables, in My.Settings or My.Namespace. The reason I ask is because I need to know certain boolean values if certain forms are open from other forms. At present I am defining Global Boolean variables in My.Application, which give the result I require.
View 3 RepliesThis is my code which i used to try this but it inserts only the last value in the listbox but i need all the selected values seperated by comma [code]...
View 2 RepliesI am coding a program that will allow the user to input 5 payrolls for Store 1, Store 2, and Store 3. The total of the 5 payrolls are then added together and shown in the respective Store's labels. A total label is also there to add up all the totals into one number. The numbers in the label must be in currency form. My problem is the numbers don't add correctly when I hit calculate. The first two numbers add together, but then after that the number just seems to subtract a random amount.
So far I have this --
Public Class Form1
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.Close()
End Sub
[CODE[...
I want my code to look at a textbox to determine which letter is in it, & assign a numerical value to a second textbox, based on what letter is in the first textbox.[code]The problem is that, when I step through the code, I can see that Form20.txtGrade1.text DOES EQUAL "C", but my code skips over the part that says Form20.txtGrade1a.text = "4". Instead, if I hover over that part, I can read Form20.txtGrade1a.text = " ".When I do not step through the code, and just run it, I see the two textboxes, with the first one containing the C, and the second one is just blank.
View 4 RepliesI've made a temp converter and i'm looking to get some validation for it. I have looked online, but most do it in a way that i don't want.
I have 3 text box's, of which i only want numerical values and nothing else to be entered into the boxes. However, i would like the validation to run when a button is pressed (in this case, the calcualtion button). I would like a messagebox to pop up stating there is a non-numerical value entered into any of the boxes and for the calculation code to not run.
Problem: I wanted data input text boxes that only accept numerical values between 0 and 999. I could check for this during a later 'save' routine, but instead preferred to warn the user at the input stage; so I chose masked textboxes - setting the mask to "000". However these boxes appear and behave differently. They have a row of 3 underscores - which I don't want - and also seem more difficult to hit with the cursor. How can I get Masked TextBoxes to appear and behave exactly as normal ones?
View 7 RepliesI am using vb.net with phpMyAdmin MySql database. While running the piece of code below, the program hangs in the for loop before the variables are assigned values from the data table(dt)...
'Check for appraisal period-----------------------------------------------------------------------
Dim sqlCheckDate As String = "SELECT * FROM tblappraisalsetting where appSetID=(select max(appSetID) from tblappraisalsetting);"
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Using VB express 2008 here. I am just wondering about the best way to store certain values like the last browsed folder even if a user closes the app and starts it again. I dont want to go the route of making a text file in the installation directory and storing the values there. Seems clunky.
View 2 RepliesI have created a program and would now like to stop users from entering incorrect values/Text inside specific textboxes. For example i would only like text to be entered when a customer name is to be inputted and if a numerical key is pressed a message box will appear saying "sorry letters only" or something in that line. Also waould like it the other way round when trying to enter text within a number only text box.[code]...
View 1 Repliesi have created one access file but i got error in the code so i can't store the values in that data file please check my code what's wrong with my code. [code]
View 25 RepliesI have a program that calculates values of a function, say f, with respect to another variable, say L.I have an array of f(L), for L going from 0 to a given integer value, say t-1 in steps of a value i.I need to export the values of this function to an Excel spreadsheet in a given column, and to do this, I would like to re-index the function f, since i is much less than one, and so the following loop I use (see below) won't work:
For L = 0 To t - 1 Step i
Sheet.Cells(L, 1) = L
Sheet.Cells(L + 1, 2) = f(L)
Next L
The first code in the loop will essentially load the values of L itself, at which the function is defined and calculated, and the next line will load the values of the function at each value of L.Since the indexes of the row and columns in an excel spreadsheet only go in steps of 1, I need to convert the indexes of the function, or the indexes to which L is loaded, so that it would be scaled so that the first entry corresponds to L=0, but the next is L=i, but loaded into row number 2, etc.
I have a module and form. Module has a structure.
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Actually values are not stored in that array list permanently. its storing temporarily and then destroying. i want to store that values in that arraylist permanently.
I am using sql in and am stuck. after "selecting * from table", how do i store whatever I have obtained from my database in a variable, for display?
View 2 RepliesOk so here's the story. I have an array of Assemblies which are initiated by [Assembly].LoadFrom() that load a number of DLL's. Upon initialising, a method called InitMain (from the DLL!) is called, which sets a number of variables outside of this method, like here:
Public Class Example
Dim C As Integer = 0
Public Sub InitMain()
C = 50
End Sub
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If I call the method Test using that same array of Assemblies somewhere later in the main application (like pressing a button or something to trigger it), it will pop up a messagebox with that says: "C = 0"Why is this? Is it fixable without any odd workarounds?
I want to create an array of constant variables for my program. But from everything I read about arrays they are handled by a number. I want to be able to pass back a variable that will hold the name of the constant as well as the value. How would you go about do that.I want to when I type the variable to have the constant name show up as I am typing.
View 4 RepliesI have text file that is saved as comma delimited. There are 3 columns with x number of rows. I cannot seem to figure out how to create an array that will store all three columns with the variable intProductArray as the length of the array. I have been opening the file with only one column and putting it into a textbox and using the lines of the textbox as the variable for length. I cannot figure out the array for all 3 columns.
Private Sub btnChoose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnChoose.Click
Dim myFileDlog As New OpenFileDialog()
myFileDlog.InitialDirectory = "c:"
myFileDlog.Filter = "All Files (*.*)|*.*" & _
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I am teaching myself VB, and when I try to run this program, I am getting "An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object." If I was to declare the variables inside each event handler, the program runs, but why won't it run when I make the scope public? Seems repititous having to declare the variables in every event handler. [code]
View 7 RepliesMy text file is a settings file and I know I will be adding more to it in the future, right now it reads "autoplay=false;mintray=false;"I am currently using probably the most inefficient way to check both of those settings:
if contents = "autoplay=false;mintray=false;" then
elseif contents = "autoplay=false;mintray=true;" then
elseif contents = "autoplay=true;mintray=false;" true
elseif contents = "autoplay=true;mintray=true;"
endif
How can I read the file, find each word from the equals sign to the semicolon, and store each of them in a variable identified by the text before the equals sign? Something like this:
contents = "autoplay=false;mintray=false;"
autoplay = "false"
mintray = "false"
Also, how can I edit the settings in the text file without having to overwrite everything every time I save to it? For instance; finding mintray in the text file, and changing mintray to true instead of overwriting the file with "autoplay=false;mintray=true;".
This is my current
Reading
Dim fs As New FileStream("C:myfile.txt", FileMode.Open, FileAccess.Read)
Dim d As New StreamReader(fs)
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please tell me what is below code doing? is it creating array with two values or its creating to string index which will take value later? [code]
View 4 RepliesI have code that will validate whether or not the input is numerical. After that's passed validation, I need to check and see if that value is greater than another.
Here's the code for the numerical validation (it works)
If Decimal.TryParse(EndOdometerTextBox.Text, EndOdometerDecimal) Then
ErrorProvider1.Clear()
Else
ErrorProvider1.SetError(EndOdometerTextBox, _
"Please enter a numeric value.")
EndOdometerTextBox.SelectAll()
e.Cancel = True
Now, I need to verify that the input for this is greater than another decimal (BeginOdometerDecimal). How can I do this? Everything I've tried fails completely (ignored) or messes up the fist validation.
I have a form with some textbox and a numerical keyboard on screen. The following code works well if only it had 1 textbox..
Private Sub botones_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bt0.Click, bt1.Click, bt2.Click, bt3.Click, bt4.Click, bt5.Click, bt6.Click, bt7.Click, bt8.Click, bt9.Click, btDec.Click
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I wish to extract numerical data from a text file and plot the data on a graph using the Zengraph classes. Each record has five variables.
I attempted to use the split function but failed to successfully get past one record.
1) How does one create an array or arrays using a text file containing many records, each with five distinct variables?
2) Is it better to create a number of single-dimension arrays or create one multi-dimensional array?
3) Is it easier to somehow convert a text file to an Excel file, with each variable in its own cell and each record on one row?