I am working in vb2008. Is there a simple way to clone the contents of a datarow in a datatable into a new datarow instance that can be added elsewhere in the table. Can I create a new instance of a datarow and set it equal to an existing datarow?
View 5 RepliesI've VB.NET function that reads data from an Excel sheet and adds rows in a Datatable.
Private Function LoadDataToRows(ByVal TableName As DataTable, ByVal Header As System.Collections.Specialized.StringCollection) As Boolean
Dim HeaderDataExcel As String = String.Empty 'Data Header
[Code].....
But no data was add to the table, only emty rows.
I've VB.NET function that reads data from an Excel sheet and adds rows in a Datatable.
Private Function LoadDataToRows(ByVal TableName As DataTable, ByVal Header As System.Collections.Specialized.StringCollection) As Boolean
Dim HeaderDataExcel As String = String.Empty 'Data Header
[Code].....
See the code below which is triggered on a datagridview row validation event where the datagridview datasource is a datatable.
The messagebox shows that it loops around as expected populating the datarow with the expected values (NOTE: There are no primary keys as this is a college assignment with specific requirement and all fields can be nullable).
I had to use ImportRows as AddRows would always error due to "This row belongs to another table" the odd thing was the values were different and again the table contains no primary keys.
The code below runs but never adds a datarow to the dataset datatable "Bookings", does anyone know what the problem might be?
CODE:
I'm trying to delete the selected row in a gridview from the datatable but it seems like it's not deleting. in if statment Table.Rows.Count = 0 is not working and I'm trying this with one row in the grid view.
Protected Sub GridView1_RowCommand(sender As Object, e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView1.RowCommand
Dim index As Integer = Convert.ToInt32(e.CommandArgument)
[Code].....
I have a listbox and its source is a DataTable, when i click a button i want to get the selected datarow somehow, maybe the index number of it so i can edit its values etc.
View 2 RepliesIn a web applicaion using vb.net as the code behind. I have created a DataSet (hdar) in the designer with a data table and table adapter (AccessRequests). I am trying to add a row to the database table using datatable.add row
[Code]...
This is bug in VB 2008
Dim dsExpre as New DataTable
Table has Two Fields (ExprID, Expression)
112,xyz
113,abc
Private Sub..........
Dim rsExpr as DataRow=Nothing
Dim i as Integer
[Code] .....
The Problem is, When i becomes 2, Table Data also becomes "q", Why....?
I have created a datatable and now i need to print it,so i did the following:
Private Sub PrintDocument1_PrintPage(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
Dim xPos As Single = 20
[CODE]...
The code works fine.But in the above code as you can see that i am printing the each rows content of the datatable one by one and after printing all the contents of a single row i am looping the code again for printing each and every row present in the datatable. So i want to know that inspite of printing each and every data present in the row of the datatable,is it possible to print the entire datarow at a time and then loop through all the rows present in the datatable?
I have a datatable with 2 columns named TimeStamp and value. After I populate the table with rows, I am using the table's compute method to get the max value like this....
MyTable.Compute("MAX(value)", Nothing)
Is there is a way to get the row (or more specifically the TimeStamp value) where the max was found?
I was wondering what the best approach is for sharing a menu across all wpf windows/views. My Application doesnt really fit the navigation model, so will probably use a Ribbon control. I am leaning towards creating a user control for the menu and dropping it on each view, but have also seen Josh Smith's msdn article, where he loads user controls.
View 2 RepliesSay I have a connection to a database. After reading some stuff I want to connect to the same database. So I naturally use the first database mysqlconnection.serverstring the password and username is not included in connect1.ConnectionString. So how can I do so? Is this by design?
[Code]...
In the code below can I use the cmd for another sql command or do I have to create a new sql command like shown below?
View 2 RepliesI am upgrading a system that has a Product Table with a Product No Field.This is a string field but most of the existing product Nos are numeric but all over the place.I want to provide a default numeric Product No when the Users are creating a new product record.All I can think of is to use the Identity Field [ProductID] and test to see if it has been used and if so keep incrementing to find the next free numerical, available No.A better solution would be to start at 1 and increment to find the first available but it looks to be several hundred records into the Table. how to find the first available number?
View 9 RepliesI'm attempting to run different tasks in there own processes, waiting until each is done while keeping the UI responsive. So far it works exactly how I want it until I try to reuse some of those processes....here is a sample of the
Private WithEvents TaskOneProcess As Process
Private WithEvents TaskTwoProcess As Process
Private WithEvents TaskThreeProcess As Process
[code]....
This is a over simplification of what's going on but it gets the point across. So it works exactly as expected, a button is pressed and the sequence starts. As each task gets disposed it recalls the StartFixing statement which then calls the next one in order until they are all done. BUT when I go to do it a second time the Disposed never fires assuming since it's already disposed. How do I recreate the same named process so it can be reused and still have it fire the disposed event?
I have a set of controls and code behind them that I'd like to reuse on multiple forms. How can I do this? I know of reusing code via modules, but I'm not sure how I can add the same controls and their underlying code. If I achieve this, will changing data on one form affect the values of another form when they're both open? For example...
Cbox1's selected item affects the choices within Cbox2, and Cbox2's selected item affects the choices within Cbox3 (and so on).
So if I do something on Form1's Cbox1 and it changes Form1's Cbox2, will it NOT change Form2's Cbox2?
Not sure if this has been asked before (couldn't find an answer), but is there a way to reuse a user.config file from a previous version of the application? For example a user.config file is stored in:
C:UsersJohnnyAppDataLocalCompanyApplicationName.exe_Url_wxcnyrmstqy3oj1qwckdjq3gjqkq4fel1.0.0.0user.config After a new version is installed it gets stored in:
C:UsersJohnnyAppDataLocalCompanyApplicationName.exe_Url_wglmejvw01nagu5t1y5yl12chynjomny1.0.0.1user.config The user then has to enter all settings again, even if the new version does not save more settings. An other problem is that although the user.config file is very small, it does get messy after a while when newer versions of the application get installed. Is there a way to clean up the unused user.config files and their folders?
It's the same problem with System.Windows.Forms.Application.LocalUserAppDataPath, that I'd like to use to save other files (containing Listview data), which points to:
C:UsersJohnnyAppDataLocalCompanyApplication1.0.0.0 The Listview data and other files created by the app can't be used anymore.This can be solved by getting the user's appdata folder with Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) and creating a new folder there with the name of the application. But this means there's one folder where the application is installed (user can choose this folder in the installer), one folder to save my own files to and one folder where VB stores the user.config file.
Can something be done about this "mess" or is this just something I have to live with?
I save the size of a form to a variable (One Size or two Integer variables--doesn't matter), and then I close the form. Before reopening the form, I set the form size to the size I saved before--which by all accounts of logic and reason should exactly the same. Except, no, it's not. On one system the form "grows" horizontally and vertically by 15 or 16 pixels. On another system the form grows only vertically 15 or 16 pixels. I'd love for someone to explain this perfectly insane, yet MS typical, behavior to me.
[Code]...
I have two datatables with similar structures that I want to make one existing row to be updated from another datatable.
For example, "tableA" has three columns: "one", "two", and "three"; with "one" being the primary key...
and "tableB" has three columns as well: "one", "two", and "three"; with "one" being the primary key.
Say there is a row on tableA that is different than a row on tableB (with a matching primary key). What I wanted to do, as efficiently as possible, is to take the that row from tableB and replace the one on tableA so it'll be modified.
I'm not sure if there's an easier way of doing that instead of using loops for setting the row's items.
created a menustrip (MenuStrip1) by dragging the tool onto my form (form1.vb). And designed the headings/items etcI have now created another form (form2.vb) within the same project.I would like to use MenuStrip1 that i designed for form1.vb in my new form2.vb.
View 6 RepliesI am very familiar with modules from my time with VB and my other programming, but what is the most commonly used practice and the best way to go about this for a website application with ASP.NET? Say I have multiple pages (in multiple directories; some in the root directory, some in child directories from the root) that will call the same set of functions and subroutines, how do I go about putting this reusable code in a place where the pages and their respective classes can call the functions/subroutines?
View 3 RepliesFirst of all, I wasn't sure whether this was VB.NET or General Developer content... It's not technically about VB.NET code, but it's not very general either since it is specifically about Visual Studio. Feel free to move it if required.A while back I realized that all of my database connection code was getting very biolerplate. had 'developed' my own method of connecting to an Access database and storing the results. Basically, for each table I create one 'Manager' class and one 'Entity' class. The Entity class represents a single record in the database and has properties for each field.
View 9 RepliesI have an application the contains several excel files bundled with it. I'm not opening the files and processing them within my application. These files contain a data-connection to reload all of the pivot-tables within each excel file. I have a 'link' on my form, that when clicked, it determines which file to open and calls a sub using filename and executing Process.Start(filename) for any excel file I want to open. I have no problems opening any one of the files and then exiting excel.
The problem is when I 'close' a file, but don't exit Excel; then try to open another file(clicking link on form)... it creates a new instance of Excel.
I know from experimenting that the fileopendialog form will 'reuse' an existing Excel instance, IF it does not already have a file open.
How can I do the same thing without using the fileopendialog?
I don't want the end-user to have access to the folders where these files live. That's why I have multiple 'links' on my form, one for each xls that already exists. I just want them to be able to click on a link and the xls file opens AND if they choose to merely 'close' a file and not exit... Don't create a new instance of Excel, but re-use the existing one.
I am trying to display value of the field ("UserID") for every row exists in datatable to checkboxlist(make the checkboxlist item selected).
I used for loop, but only the field value from last row of RoleUsers table is selected in the checkboxlist.
Here is my code
Private Sub DisplayRoleUser()
Dim conn As SqlConnection
Dim cmd As SqlCommand
[Code].....
I have a datatable and I apply a filter to the defaultview.rowfilter property of that datatable. If I then loop through the rows collection of the datatable, will I only be able to see those rows that the filter applies to, or will it loop through all the rows?
View 6 RepliesI am working on a project that takes an xml schema and xml data files and places them into a DataTable, the 2 files are generated from a working table that i have written to disk. I wish to load these 2 files into a DataTable. Here is What i have
vb.net
Friend Function CreateTable(ByVal tableName As String) As Boolean
Dim table As New DataTable(tableName)
table.ReadXmlSchema(tableName & ".xsd")
[code]....
this however produces the following error on line 3
Quote:
System.ArgumentException was unhandled Message=DataTable 'get_item_list' does not match to any DataTable in source.
get_item_list is the parameter passed into this function (tableName)
I have a datagridview bound to a datatable setting its datasource property to the datatable. I would like to have a child form that contains a list of columns associated with the datatable that contains a checkbox that will allow the user to hide and show the columns ( I do not know the best control to use here) (I assume this is the easy part as All i need to do is loop through each of the datatable's columns to get the column name)
now I would like save these visible columns on some event like form_closing so that the next time the user opens the form up it will remember the settings
I came across a problem with using a BindingSource as my DataGridViews.DataSource. Whenever I applied a filter to a column in the BindingSource and the user makes changes that don't match the column filter the DataGridViewRows would automatically disappear. A similar thing would happen when applying a Sort to a column. If the user made any changes the DridGirdViewRows would automatically sort causing rows to be moved around. This was not ideal for my application and there isn't anyway to stop this from happening with the BindingSource.
To correct this issue I have to use subsets of data. I use a DataView to apply the filter and sort to the main DataTable, which creates the subset DataTable.The problem is when I use the DataView.ToTable method I loose the Primary Key and RowError information. So I have to reapply this information everytime the user filters or sorts the DataGridView.Is there a better way to get a subset DataTable?[code]...
I have a datatable that has a resource in one field and hours used in another, it looks like this -
Resource Hours Used
Manager 1
Accountant 1
Field Staff 2
Accountant 3
Manager 4
Manager 1
Administrator 6
Field Staff 4
Manager 0.5
Administrator 1
What I want to do is be able to create a summary of the data table above that groups multiple occurrences of a resource and adds up the hours used for that resource, creating a summary that looks like this -
Resource Hours Used
Manager 6.5
Accountant 4
Field Staff 6
Administrator 7
Is there a simple way to assign a populated datatable's columns to another empty datatable? That is, I want to copy a datatable's structure only but not its data.
View 6 Replies