How do I call a function with System.Threading with parameters and get the return? Normally my code would be:
StrInput = GetString("A")
How can I do this with multi-threading? Is it possible to call this function several times without having to create a new thread each time or a sub that I then run as a seperate thread?
When a json result is returned by the controller the object name seems to be missing, I normally wouldn't mind but the flexbox jquery plugin requires the json result in a particular format.
[Code]...
There is a stored proc.. Which was returning to result sets..
Ex:
select * from table1
select * from table2
If I get this data to a Dataset, Definitely I will get 2 data tables with index (0,1)..But what if go though a Datareader? I had checked that just now.. And I got a result of first result set (i.e Table1 in our example)..
I have the following value 48.81, it comes as a string from the database, I need to convert it to decimal, I'm using:
Dim Seconds As Decimal = Convert.ToDecimal((Coordinate.Substring(4, 5)), CultureInfo.InvariantCulture)
I'm receiving 4881D and I need 48,81
I thought CultureInfo.InvariantCulture was going to help me with that
EDIT:The coordinate value is 675900.244.I'm "spliting" it like this:
Dim Degress As Integer = Coordinate.Substring(0, 2),
Dim Minutes As Integer = Coordinate.Substring(2, 2),
Dim Seconds As Decimal = Convert.ToDecimal((Coordinate.Substring(4, 5)), CultureInfo.InvariantCulture),
[code]....
This is the value of the coordinate in the database?
The following code in C# gives result "228452386"
UInt32 a;
int k = 0;
a = 0x9E3779B9;
a += (UInt32)(url[k + 0] + (url[k + 1] << 8) + (url[k + 2] << 16) + (url[k + 3] << 24));
After above code is ran, "a" contains "228452386" But the following same code in VB.Net results in "Arithmetic operation resulted in an overflow". Basically the last statement is returning value "1868983913" so the runtime error is generated.
Dim a As UInt32
Dim k As Integer = 0
a = &H9E3779B9UI
a += CUInt(AscW(url(k + 0)) + (AscW(url(k + 1)) << 8) + (AscW(url(k + 2)) << 16) + (AscW(url(k + 3)) << 24))
note the variable "url" in above code could be any string and it is same for both codes.
EDIT:When I run the following statements in both C# and VB.Net than they both return same value
C#
(UInt32)(url[k + 0] + (url[k + 1] << 8) + (url[k + 2] << 16) + (url[k + 3] << 24))
VB.Net
CUInt(AscW(url(k + 0)) + (AscW(url(k + 1)) << 8) + (AscW(url(k + 2)) << 16) + (AscW(url(k + 3)) << 24))
Both statements return value "1868983913" for "url" "info:microsoft.com". But when I run complete statement with a += ..then VB.Net gives error while C# returns value "228452386".
I have an ASP.NET web application (VB.NET) using an Oracle database. On an insert, I need to get the identity of the inserted row back. I am trying to use RETURNING, but I keep getting a value of 1 returned.
Dim strInsert As String = "INSERT INTO L.TRANSACTIONS (LOCATION_KEY, TRANS_CREATOR, TRANS_EMAIL, TRANS_PHONE) VALUES (:location_key, :trans_creator, :trans_email, :trans_phone) RETURNING TRANS_ID INTO :ukey"
[Code].....
My brain may just be fried since it's the end of the semester, but my teacher kicked this back to fix and resubmit...she said that I am "returning the name of your function rather than your variable name".
Here is my code for all 3 forms.
code:
These are forms to calculate the cost of getting a cell phone package.
I am currently having a headache on how to solve this problem that i am facing. here is the situation: I have a combobox and a list box on the main form. The combobox will get the data from the ms access database. In the database, i have the details of a person's IC, Name and DOB say for eg on one entry I have D215311523C,SHAWN,13/04/1987 So now, my combobox on form load will show the list of dates in the database to allow the user to search base on the date itself by clicking on the selected date. So when the user clicks on the particular date say 13/04/1987, people in the database whose birthday is 13/04/1987 will be shown on the listbox.Meaning to say if i have 3 entries whose dates are the same 13/04/1987, 3 entries will appear. If there is only two entry, then two results will be shown. But now, when i do a single click on the date, one result will be shown. That is correct. But the problem is when i click on the same date again, three of the same results will be shown on the list box. that is it will display : 13/04/1987 13/04/1987 13/04/1987 which is not the case. Then it will show more duplicates of the same results if i click more times on the same date which should not be the case.
Dim n As Integer
Dim numbers() As Integer
Dim StartFrom As Integer
Dim EndAt As Integer
[code].....
I am using a datagrid in my where i am having four columns. In first column the parameter values are entered and in the second column measured value is entered and in third column the nominal value is entered.Inthe fourth column the result is displayed by subtracting the measured value and nominal values. I am doing this calculation in Datagrid cell validated event. What i want is,there will be many rows in the grid,when typing the value in the third column the corresponding result will be displayedin the rowof theresult column,save button will be displayed while the form loads,when the calculate part is completed that is there should not any cell of the resut column empty then i should enable the save butto.
View 2 RepliesI am encountering the following issue So i have a device that sends stuff at the serial port, i then parse it and put it into an array of bytes like that:
Dim HCI_Command_Rcvd_Byte() As Byte All good till here What i wanna do is make an array and put this result every time the serial port gives me a new result, for example:
[Code]...
Basically what i wanna do is let the port parse the messages, fill in the array with the result at an empty spot in this array and then i will have a separate thread that will look in into this array in each non empty space and after it looks into the non empty space it will use or discard the info and also mark this space as empty (after it checked)
I just read about DataSet in VB.NET, it uses disconnected concept. My question is: if my apps has "List All" button that query data from 1 table in the database, and that table has "very very very" many rows, so my DataSet will be filled with those data and eat up memory. Can I limit the data that being put to the DataSet from that query? But I want to be able to retrieve the next data from the same query if the user want to see it?
For example:
I have 1000 rows in my database, and i query all of them. But I just want 200 rows being inserted to my DataSet, but if the user want to see rows number 201 and so on, I want to be able to retrieve the next 200 rows, and so on. So it just like cutting those data into a group of 200 rows. Can I do this with the concept of "disconnected" of the DataSet?
I have set up a method in vb.net and in xcode for encrypting a string using as far as i can tell the same parameters for an AES encryption.I've looked all over the place but cannot find information on whether they use the same encryption algorithm and settings.
this is the vb.net code:
Dim encryptAES As New AesCryptoServiceProvider()
Dim encoding As New UTF8Encoding()
Dim encryptor As ICryptoTransform
encryptAES.Key = encoding.GetBytes("12345678901234567890123456789032")
encryptAES.IV = encoding.GetBytes("1234567890123416")
encryptAES.Mode = CipherMode.CBC
[Code]...
What is multithreading and how do i do it in vb.net?
View 2 RepliesI am using an Application server for calling Oracle Reports and I have a URL to call the report. When the report is called the server converts it into PDF but when report contains large data it takes a lot of time to load. I want to do in asp.net that when I call the report url it opens the PDF file and copies it into the root of my web folder. The next time when I call the URL it opens the PDF file and creates a new PDF on backend for next call. I have made this function to download file
[Code]....
In which situations we can do the multithreading and deadlock concepts. can give some examples
View 4 RepliesBasically I am making a proxy testing program. A user can supply a list of proxies to test. What i want to be able to do is have them be able to specify how many threads they want to run. Then have the program go through the list testing each one using the amount of threads supplied. Really not sure even where to start on this. Threadpooling?
View 3 RepliesWhat does common data or data that's in a common, look and is treated by multithreading? I'm quite aware that acess to such data would have to be synchronized, but beyond that is it acessible?
"MODERN PROGRAMMING is deficient in elementary ways BECAUSE of problems INTRODUCED by MODERN PROGRAMMING." Me
I have a class with a background worker in it that does some tasks on a separate thread. I want to fire some events from the background worker thread to the 'main thread' of the class, so that when using this class your not obliged to go make invoke calls for every event handler your using.I'm at a loss of how to do this though. When having a similar problem in a form of usercontrol I always use Me.Invoke, but this method is not present in a class inheriting system.object.
View 1 RepliesI have a screen that checks for alerts every 30 seconds by looking up outstanding issues from a database.When there is an alert, an audio file is played depending on the alert.It takes 1-2 seconds to grab this audio file which caused an issue with global screen freezing, so I added multithreading where it plays the sound file. This seemed to work fine.However I am new to multithreading and am not sure if I'm working with it efficiently..I have simply declared the sound-playing function as a thread at the top:[code]I am unsure if starting and aborting the thread is the right way to do it. However if I suspend or make the thread sleep I would have to determine whether it has been run before.
View 18 RepliesI have read many articles on multithreading over the past few days and so far I'm fairly comfortable with how it works. I am now working on my actual application, and have come across a few design issues that I'm hoping somebody has experience with.The basic premise of the application is simple. A database filled with files names and a "converted" field that has a 1 or a 2 in it (1 for unconverted, 2 for converted). The application loops through every record where "converted" = 1, retrieve the file and convert it.
My single threaded application works fine, except its far too slow. Due to the huge amount of rows in the database (4 million+) and the time constraints on the project, I have decided to run as many threads as the hardware can allow to cut down on the timings.So, the dilemma is accessing database records and which threads should grab which record and how.
I have a function in my program that adjust sales for multiple days. Sometimes it needs to adjust up to 3 months and the tasks takes a while so I decided to split up the work between multiple threads. The way I have it working is say I need to adjust 3 months. I have the first thread adjust sales for the 1st month, the second thread adjust sales for the 2nd month and finally a third thread that will adjust sales for the 3rd month. Since all three threads are performing the same tasks except for different date range they use the same procedures. Within those procedures I make a call to the database to extract the sales for the given month. At some point it seems like the threads start to use the same SQL Data Objects because I am receiving the below error."There is already an open DataReader associated with this Command which must be closed first."Below is the first procedure that is ran by each thread up to the line where it errors out.
Private Sub Process_Adjustments(ByRef objAdjustBillCodeThreadParameters As clsAdjustBillCodeThreadParameters)
Dim cmd As SqlClient.SqlCommand
[code]....
So all three threads call this subroutine and the first thread does the data fill with no issues and then sometimes even the second thread does the data fill with no issue but then the third thread crashes and produces the above error. It seems as though the threads are sharing the same SQL Objects when all objects are local to the sub and I always thought each thread had it's own memory to work with. So I thought each thread would call the sub create it's own objects in memory, but that does not seem like what it's doing. I have other multithreading processes in my application that work perfectly fine, this is the first time I am attempting to multithread in this manner where I am using the same procedure within multiple threads.
Just thought of something that I might be doing wrong. The subroutine in question is in the same class where the threads are created. Should the subroutine be in it's own class, and therefore each instantiation of that class?
I try to use Multithreading with VB 2005. I added a Listbox to main form and i tried to fill ListBox with 2 threads. When i executed code it told me that this is unsafety operation becasuse of ListBox is created with Main(Form1) form.
Is there anybody who has such simple multithreading example with Mutex or such lock mechanism?
what is the right way of Multithreading in visual studio 2008.
View 1 RepliesI m making a project in which it check website about there status (Online / Offline) through there status code and when project is in processing it hang's until the whole line of code complete
[Code]...
I'm using the WIA Aut. Library [URL] , trying to capture photos from 5 digital cameras (Nikon D90) USB-connected to my pc. Now, I partially achieved my goal, what I do is:
- loop through the attached devices, connecting to every camera;
- fotocamera.ExecuteCommand (WIA.CommandID.wiaCommandTakePicture) ;
- other image processing operations...
Everything works fine but... the workflow is camera1 -> connect -> grab pic. => camera 2 -> connect -> grab pic. => camera 3.....
[Code]...
I'm using the WIA Aut. Library [URL] trying to capture photos from 5 digital cameras (Nikon D90) USB-connected to my pc. Now, I partially achieved my goal, what I do is:
- loop through the attached devices, connecting to every camera;
- fotocamera.ExecuteCommand (WIA.CommandID.wiaCommandTakePicture) ;
- other image processing operations...
Everything works fine but... the workflow is camera1 -> connect -> grab pic. => camera 2 -> connect -> grab pic. => camera 3.....What I'd like is to make them shoot all at the same moment (...why? well, D90 waits around 1 sec. after a shoot... 1sec * 12 cameras * 500 photo sessions.. :'( )I told myself... what's the problem? You can create "shooting-threads" while looping through the device then launch 'em all.Done.It's still in a 'serial' way... :-(((Why? is executeCommand() a synchronized method? If I madly-fast click on two 'grab pictures' button of windows XP WIA dialog it works.. Is there something about .NET multithreading I don't know?
My application will creates an Excel from DB, creating an excel file takes few minutes of time and till that time the user dont want to wait for the excel to complete, he should start working with the application. Once the excel have been completed the appilcation should po-up message saying, 'Report Sucess'. can any one tell me how to do this, whtr background thread will help me in this ?
View 1 RepliesMy question is to add two numbers up using threads or multithreading. Here is what I have:
Module Module1
Sub ThreadA()
Dim I As Integer[code].....
Is there a way I can use this somehow to add two numbers up?
I am looking into using a producerconsumer threading pattern to run through a list of strings that i retrieve from a database and then am going to run powershell commands against. As the powershell commands can be quite intensive i only want to spawn 3 threads at a time and then wait for one thread to finish before doing anymore. I looked into the treadpool but it looks like it is used for more lightweight processing.
View 3 RepliesI want to download some imagefile from a multilinetextbox and right now i m using this code
Multiline textbox contains :
[URL]
Code 1 :
Code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim ary() As String = TextBox2.Text.Split(Environment.NewLine)
[Code]....
because in both cases it will download file one by one and i want to do my job as fast as possible by sharing the multilinetextbox data among set of thread's but how to do i dunno
Like if i multilinetextbox contain 100 image file link and i want to run 3 thread at a time then these 3 thread will share/Access the multilinetextbox data what will be the my final code ?