Make Loop In Program And Calculate Time Taken To Complete Loop?
Nov 23, 2011
I am constructing a program, i am new to Visual Basic, but i have past programming experience. I was wondering if anyone knew how to form a loop that could...lets say calculate the answer when two numbers are added together,and it would repeat this thousands of times, etc. And if there is a way, would it be possible to calculate the time taken to complete this loop.
Makes the following statement about the code below:
**"The computer evaluates the loop condition in the Do...Loop statment to determine whether the loop instructions should be processed. In this case, the inputsales <> String.Empty condition compares the contenst of the input sales variable to the String.Empty value. As you know the String.Empty value represents a zero length, or empty, string if the inputsales variable is empty, the loop condition evaluates to True and the computer process the loop instructions. *If on the other hand the inputsales variable is not empty, the loop condition evaluates to false and the computer skips over the loop instructions.
Based on the code I think it is the opposite: ...that while the inputsales value is not empty it should evaluate to true and process the loop and if it is empty it should evaluate to false and skip the loop?
Today I investigated a logical bug in our software and figured out that this is related to the way VB.NET thread variables inside a loop.Let's say I have the following code:
Dim numbers As New List(Of Integer) From {1, 2, 3, 4, 5} For Each number As Integer In numbers Dim isEven As Boolean
[code]....
The problem is that isEven is declared but not assigned.In this specific case, it would be correct to write dim isEven as Boolean = false but I haven't done this.In VB.NET, a variable that is declared inside a for loop keeps its value for the next itaration. This is by design: [URL]but this is also dangerous pitfall for programmers.
However, until now, I haven't been aware of this problem/behaviour. Until now.Most of our code base is C# anyway, which doesn't allow the use of an uninitialized variable, so there is no problem. But we have some legacy code that is written in VB.NET that we have to support. So the best thing would be to generate a warning or even an error in this specific case.But even with Option Explicit / Option Strict this does not generate a warning / an error.Is there a way make this a compile time error or maybe a way to check this with FxCop?
I am creating a program for which will calculate the time taken for a user to make a number keystrokes. I want to start the timer running from the beginning of the first key stroke and end on the final keystroke. Each keystroke has been linked to a label which will change colour according to whether the key has been pressed. When the keystrokes have been finished I want to save this timespan in a field in a database. To test that the timer is running I have made a messagebox which will show the time taken however it is constantly showing zero and the label for the final keystroke is remaining in the keydown colour.
Public Class Form1 Dim dteStart, dteFinish As Date Dim span As TimeSpan
I'm looping through items in a listview. For each item, it deletes a file containing information stored and re-writes it with new information from the listview item.
I am having problem with the coding of this (endless loop) and formatting of summary boxes before tests are complete that should not happen. (the overall goals is to have a separate validation procedure that does not calculate or dat displays are not performed until after call function is complete and valid. The validation that takes place are that two boxes are filled in - one is text and the other is a numeric value. (using vb 2008)
I'm looking for a way to calculate an average from a input integer within a loop. When the user enters something like -90, the average will be calculated using the previously input numbers.
I need to change it so that this contains a loop to calculate the earnings. vb.net Private Sub btnCompute_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCompute.Click 'Compute total earnings at retirement. 'get 5% raise per year, retire at age 65. Dim name As String, age As Integer, salary As Double [Code] .....
I have written a function that gets the alexa ranking of a given url, now this function works perfectly but I want to loop through a ListView of urls and grab the alexa rank of each item (url) with my function.The code works great if I put a MessageBox in the loop to test that the function is returning a value but when I remove the MessageBox the loop does not work.I need it to loop through adding each result without a MessageBox stop in each loop.
vb For Each Item In ListView1.Items Dim result As Integer result = GetAlexaRank(Item.Text)
Is there any way to loop through the applications that run at a time (the application list from task manager) and get the application's caption?
At a moment I have two instances of "acad.exe" but they will have different application name and I have to choose one of them, but I don't want to close the other one.
If I use the process list I get only the "acad.exe" name and I cannot differentiate between them.
The code below finds a string from a text file and, if the correct month, - Monthcheck1, adds it as an item to an unsorted ListBox. I want to run through the text file again to find data for the next month. If I repeat this code for MonthCheck2, nothing is added. My question is: What is the convention for looping through the same file a second or third time?
I checked the contents of the array at the end and it only held the last records within the text file, which suggest that it is overwriting the array, how can i prevent this?
So I'm kind of new to VB and am just playing around with a little project, I currently need a loop that is constantly checking the systems clock to see if it's equal to a certain time.
While Not myTime.Hour = 24 If TimeOfDay = newTime Then nfi.ShowBalloonTip(15)
How can I loop through each date in a given time period so that I can add those dates as a column name in a table. I want to create datatable with the person's name and hours he worked in a given time period. The user will select the dates and I want to show each day/date in that table as a column name.
I wrote a program which loops through a very long CSV file (50 meg) and parses the data as it goes.Sometimes, the program aborts and I get the following message:The CLR has been unable to transition from COM context 0x37a090 to COM context 0x37a200 for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages. This situation generally has a negative performance impact and may even lead to the application becoming non responsive or memory usage accumulating continually over time. To avoid this problem, all single threaded apartment (STA) threads should use pumping wait primitives (such as CoWaitForMultipleHandles) and routinely pump messages during long running operations.
I know its going to take a while. There are several hundred thousand lines of text in the file that this program is reading. I am not sure exacly waht the message means, but my program seems to work fine other than the message. odd thing is sometimes the message doesnt always pop up..
I'm using visual studios 2008, VB9 and I am trying to write an app that basically performs calculations on a set of data input by a user. During the calculations, I want to display the data at each step, and have it retained in the display area on the GUI (not overwritten by the next data being displayed).
For example:
UserInput = 1 Do UserInput += 1
[Code]....
I tried this, and other loop structures and can't seem to get things right. The actual app is a bit more sophisticated, but the example serves well for logical purposes.
So I made a simple patform game where the player has to jump quickly while the platforms move to the bottom of the screen, as to not touch the bottom of the screen. But, I need to know how to create a loop to loop the locations of the platform. This means that after twenty or so platforms, the same platforms come up again, so that the player will have an "endless" game. I've declared all the platform's locations relative to the location of the first repeating platform:
I'm trying to get an in a loop to accept a value and add it to a list each time okay is pressed. For some reason, I have to add a value twice for the input to be added to the list. For example, if i enter the string "hello" in the inputbox and click okay, it doesn't add to the list, but if i do it a second time, it goes in.
Here is the code for it
Do Until lstCourse.Items.Count = CDbl(txtClasses.Text) InputBox("Enter Course Number", "Course Number") strCourse = InputBox("Enter Course Number", "Course Number") lstCourse.Items.Add(strCourse) Loop
I am trying to loop through a dataset and process n numbers of records at a time.For example lets say I have around 240 records in my dataset. I need to loop through the dataset and then create a new batch of 50 records. so for the dataset which has 240 records I want to create 6 batches. Out of these 6 batches, 5 would have 50 records and and last batch would have 40 records.
What I want to do is I want to post to different referers one at a time and of course the links will be provided by a richtextbox(i.e. richtextbox1.lines(i) ). I will use only password(which will be chosen by the user from a combobox(combobox1.text)) because the username is harcoded. This is what so far ive come up with but it always gives me the result of the first line(or referer) from richtextbox1. I think there might be a problem with my "FOR" code.
if i have big looping, and i want to print it result real time, how can i do it?(it look like when we scanning with antivirus, then the label that contain location that scanning change real time)[code]...
A few years ago I have been busy creating this application but it didn't succeed, now Im coming back to it and similar problems occur. Basically I use SetPixel on a given window to draw a line, work fine, but the line goes away as the window redraws itself.The problem: I have been putting timers and threads on it to make sure the line is being drawn. Is there any way to make a loop to make a certain thing happen about 10-30 times without taking in too much memory/CPU?