how do you save data stored in an array of records (structure) to a text file using StreamWriter? I currently have
Private Sub btnSaveToFile_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSaveToFile.Click
Dim sw As New StreamWriter(New FileStream("EmployeeDetails.txt", FileMode.Create, FileAccess.Write))
For Each record As EmployeeType In employees
but it doesn't work. My array is fixed and currently has 3 elements (for testing purposes). If I enter two records and add these to the structure I get the following data saved to the text file:
How do I stop unused elements of the array being included when writing to file? Should I use a dynamic array instead and if yes, how do you use dynamic arrays with structures?
I am trying to convert a VB5 program to VB2010 so that I can continue to support it on my new PC. My copy of VB5 was an upgrade from VB3 which was an upgrade from VB2 which came on floppies, so I can't just install every preceding version as my new PC doesn't have a floppy drive.I have accepted that I will have to design all the forms from scratch (whatever happened to twips?) and will have to go through the thousands of lines of code line-by-line, but I have hit a brick wall when it comes to random access files. One such file is defined in the Declarations section of Module1 thus:[code]....
I soon found I had to change Type to Structure, but then in the declaration of transrec, transtype acquired a wavy blue underline with the error message: "'transrec' cannot expose type 'transtype' in namespace 'Treasurer_2010' through module 'Module1'.So if I can't use the structure in the module in which it is declared, where can I use it?
how to read and write random access records in .NET. Now I know random access files are dead and the response on every query I found with google/bing/yahoo searches was don't use random access use Binary serialization but I can not. I have a situation where I need to read and modify 256 byte records in a file that is used by another application.
Now for a bit of background the file is made up of 27 fixed length records of 256 bytes. Each of the records has a separate structure consisting of 30-120 fields. The proplem I am having is I can create the record structures but when using the FileGet method I am receiving an error. Now I have found samples that showed the same format I am using that claim to work.
The error I am getting is Option Strict On disallows narrowing from type 'System.ValueType' to type 'ProgramName.ModuleName.Record' in copying the value of 'ByRef' paramater 'Value' back to the matching argument.
The basic layout (simplified) is as follows:
Code: Structure Record <VBFixedString(6)> Public SomeParam as String Public SomeNumber as Short
Now the overloads for FileGet show all of the data types including Object. But I have tried various methods to retreive the 256 byte record but without success. Do I have to actually read each of the several hundred fields of the structure one by one? Or am i overlooking something (I have been known for this in the past)
Or (and I'll kick myself if this is the only way) do I just have to set option strict Off in the module and the code as above will actually work.
I would love to be able to just ditch the random access file but I have to keep it for compatibility with several other applications at this time.
I have 15 years' worth of files (approx. 10,000) that were created using VB6 structures and stored using the random access method. I am trying to write a conversion routine that will read the old structures and put them into a new format that is more compatible with the .net environment. I have not been able to successfully read any of the old files using the tools available in .net. Each file starts with a header record structure. The header record tells me how many tags are in the file. The next record (ie record number 2) is the first tag pointer record in the file.
There are num_of_tags of the pointer records. Each pointer record has the string that holds the tag's 'literal name and two long integers that tell where in the file this tags records are. Those actual records are stored as History data structures, [Code]
I'm working with random access files. I created a module and in it put the
Structure PersonData Dim Name as String Dim Age as Integer[code]....
The problem is strange... it will let me input string lengths of 3 for Person.Name and Person.Description and it will save correctly, however, the moment I try and lengthen the string (or even if it's longer than 3 to begin with), I get a 'bad record number' error.
I have recently decided to give .net another chance, but i have a few questions about it before i get really into it. RE: Files, I use random access files to store data as opposed to databases (namely i don't see the need for a database for storing so little information(records <200 max) knowing that it is an older system and less "cool" i don't care...) Will vs2010 express read, write to random access files? Would it be done kind of like vb6 (which is my current vb version)? I will be needing to print the text of rich text boxes, is vs2010 express capable of doing this?
I have a VB 6.0 application that works with random data files... Now I have to create a .Net 4.0 application that generates and update random data files.... Net Framework 4.0 can work with random data files ? Does it support again this old tecnology ?
I have problem with saving data to access db, im using vb.net2008 and access 2007 in WIn7, in form is datagridview and binding navigator when i click to save and close app and then open database in access 2007 the last row is not saved this is default save action [code]...
I can save my data to access database and in the access database field I set it to date/time.But problem is when I get the value out from the database.. the format is always month/day/year hour:minutes:seconds example today: 5/2/2011 12:00:00..How to get the value into listview becoming May/2/2011 without the hour..Here's my code to get it from database ListView1.Items(i).SubItems.Add(dt.Rows(i)(14).ToString).The second problem is.When I would like to edit, how can the datetimepicker get the listview value ? [code] info: using access 2003 (.mdb) the Date of Birth field has been set into Date/Time.
Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveAsToolStripMenuItem.Click timedate.Stop()[code]......
The problem is that if I save a file I get "myfile.GDL" if I overwrite that I get a new file "myfile.GDL.GDL" ect.the other problem being that the filtering in the windows save/open dialog wont show .GDL files unless I select "all files".
i am newbie in vb. and i facing a problem in database update into the access database. well, because of my windows have combobox and textbox. i dont have any difficulty in textbox update into access database, but i face a difficulty in combobox. and my combobox have 2 item in it. anyone can teach me? anyone can provide me some coding example and detail examplation. because i am the type who look through the coding and learn form it.
I have a Listview with 5 columns. It display data taken from 2 textbox, 1 combobox, 1 datetimepicker and auto generated number. I want to save all these data to a database. While trying with my code I was getting some errors. I add my whole project here . Below is my code -
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click For x As Integer = 0 To ListView1.Items.Count - 1 CMD.Connection = CN CMD.CommandText = "INSERT INTO SaveData (CatID, Item, SubItem, Date, Amount) " + _
I have problem when save data at ms access database (save multiple data). VB.NET Dim prodid As String Dim charga As Double = 0 Dim iqty As Double = 0 Dim idisc As Double = 0 'simpan detail For i As Integer = 0 To dg.Rows.Count - 1 [Code] ..... The field is too small to accept the amount of data you attempted to add. Try inserting or pasting less data.
I have a VB 2010 program with a single-table Access Database.I have selected the option to copy the Access Database to the output directory.When doing so, the program copies the original database to the inDebug folder.I want the original (NOT the copy) to be modified when the program is being tested.Also, when I attempted to publish the program and run it to test, I got an error which was sourced to be a temporary file (which was the database) that was missing.I think this is a reaction from the "Copy Always" option.
I'mvery new to VB2008 and have basically no idea regarding much of coding. I have attached a copy of my form. Basically, I have a db named "employee.mdb" with table "Employee". It has 3 fields Name, Dept and Designation. I want to connect my db with the form and want the following functions (when the respective buttons are clicked)Add: Add a new record to the db and save it without overwriting an existing record.Delete: Delete the selected record from the dbSave: Save all details<<: Move to the previous record>>: Move to the next record. I hope I have explained myself clearly
I am doing a project on creating a database using vb.net. I need to be able to add records, save, delete and retrieve these data. I am a beginner so far I have created the design I need to be able to link many forms such as order form, find customers, add customers etc. How do i go about this.
I am looking for ways to retrieve data from textfile and save it into access database. Currently, I am doing a attendance record project. I need to save the attendance record which is given in a text file to the database. The version of VB i using is VB 2008.
The content of the text file look like this: E010,2009/06,06/29/2009 7:44:45AM,06/29/2009 15:00:55PM,JUR E022,2009/06,06/29/2009 7:44:45AM,06/29/2009 15:00:55PM,JUR
I tried to create a class and store the record but it just don't work.
i have a form with some text boxes on, for now im just testing with one of these boxes 'Customer Name' So i made a database and made a two column table with ID and Customer Name. then in my pogram i put this code:
Dim inc As Integer Dim maxrows As Integer Dim con As New OleDbConnection
into my save button, however i get a 'oledb exeption was unhandled' ''Syntax error in INSERT INTO statement. on the line da.Update(ds, "Customers")
I'm currently attempting to save data inputed into a data grid clicking the "save" button. My problem is, I also have another DB opened in the same window that also needs to be saved. The second database is pulled up by the contents of a text box, so there for it has no real Dataset to call on. It looks something like this.
I try to run the update command it always throws the exception "Cannot find table 0" or "Update unable to find TableMapping['Table'] or DataTable 'Table'." I tried declaring the connection the same way as the code above and then simply calling the da.update(ds) but it wouldn't do anything.
We have developed an application using Visual Basic .NET as the front end and Microsoft Access as the back end. If we run the application on Windows XP we can write records to the database but when we run it on Vista it does not write records to the database.
I have just completed an upgrade of a VB6 app to VB.net (2008). Everything works as it should except for one (essential) part. I cannot open more than one instance of the built app without getting a file access error. Now don't laugh but my program uses Random Access files to store the data (i know, i know the 1990's called and they want their programmer back). Anyway I've been using this method since the early 90's and it's never let me down. Until now that is. VB6 allowed any number of users to access the files but for some reason VB.net gives the following error: The process cannot access the file "C:lah blah" because it is being used by another process.
I am using MS Access 2007 as database and VB 2008 to build an application to show the content of 2 tables as a single table.I have two tables in MS Access and i have linked both the tables using "ID" as primary key(1st Table),foreign key(2nd Table). I used Query Wizard to show the data of both tables in a single table(3rd Table).I am able to view the content of all 3 tables using datagridview in vb 2008(Using Code), but i am unable to add,delete,save and search the content of the table using code. My concern is,i will be able to do all these operations using codes only.Would you please help me out in this.
I have added some files that I need to be downloaded to the Application start up path. So I set Build Action as content now the files have been copied some where C:Documents and SettingsTestUser.ANNAMLocal SettingsApps2.0DataHVDRBMY5.8AA858AT9VM.TNP est..tion_2d7cfc137d9c2c74_0001.0013_432bd4561850d290Data How can access file from the application. My problem since it is a dynamic path will it be same folder count so that we can use like ....Data Some think like this
New to VB... I am trying to access .SYS (system files) located in the following folder path (example) My Database NameVIEWSSYSTEM VIEWS in the Object Explorer of my SQL Database. In walking through the Data Source Configuration Wizard for data connectivity I select DATABASEVIEWS and the SYSTEM VIEWS sub-folder is not available for selection. In general: What is the best method to access System Files using VB Data Source?