I have a datagridview bound to a datatable via a dataview. The user is allowed to edit cells in the datagridview, thereby editing cells in the datatable. I recently found that if the user editted a cell, then closed the form without ever clicking on a different cell (thereby causing the current cell to commit), the change was vanishing because the editted contents of the cell were not being saved back to the datatable.
This was only happening if the user closed the form. Clicking on any other control on the form also caused the cell changes to commit. After rooting abut in the DGV properties, it appeared that all I needed to do is add the following code to the Form Closing event handler:
If Me.dgvCurrentRedds.IsCurrentCellDirty Then
Me.dgvCurrentRedds.CommitEdit(DataGridViewDataErrorContexts.Commit)
End If
Sure enough, this caused the change to be registered in the underlying datatable. However, it was then getting obliterated by a different process, so I went looking for the source of that problem, and eventually tracked it down to this:
While the preceding code is causing the datatable to receive the new information, the datarow that has been changed still has the status Unchanged, even though it should have the status Modified since it actually has been modified. The fact that it appears unchanged causes some other code to obliterate the change, but that's irrelevant.
The question is, why is the row status UnChanged when it certainly has been Changed, and is there any sound way to force the row status to update?
I want to compare differences between two tables in my database with identical schemas.
vb.net DataTable1.Merge(DataTable2) Dim changedRows As DataTable = DataTable1.GetChanges 'changedRows is always Nothing. Why???
The DataTable1 is updated with rows from DataTable2 correctly. i.e. missing rows are added and datarows that don't match are updated. But the RowState of each row is still unchanged. I need to have the rowstate (added/modified/deleted) so that I can update the database table.
I've got lots of textboxes bound to a Dataset. When I make changes to a textbox with the mouse/keyboard the rowstate becomes changed - and when I do the .EndEdit and update the row it goes to the DB.
I've got some textboxes that get changed in code. When this happens the rowstate remains UNCHANGED. Updates to the DB never occur.If the textbox is changed in code and I also change another textbox in the UI then both changes make it to the DB.
I've verified that the "in-code" changed field in the dataset is actually changed - but the ROWSTATE is still printing as UNCHANGED.Here I'm showing that field 29 has changed to "blank" - but the RowState still is UNCHANGED. Why would changes to the .Text property of a bound control does programatically not change the row state?
Seems a google for this does uncover issues like this - but nothing that's helped me fix it so far - here's one link I can't make sense of[URL]..
I have a form with textboxes for input. I have coded the Exit button to display a message box that asks the user if they want to save any data in the textboxes before exiting the program:
Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e
[code]....
The question I have if the textboxes are blank (nothing has been entered), how do I code the Exit button to close the program without displaying the message box asking the user to save the data.' Save the numbers. Call the btnSave_Click procedure.
I've got my code to delete rows out of the database when the user clicks on the Delete button in my GridView, but the GridView isn't updating to reflect the new data changes.
EDIT 1:Did some stepping through the code and found that e.CommandArgument is not getting a value in grdQuestions_RowCommand
EDIT 1 (Revised):The fact that e.CommandArgument wasn't getting a value was my mistake. I'd changed the way it's value was being assigned without removing the previous method.The code runs through grdQuestions_RowCommand and then goes into grdQuestions_RowDeleting and then executes GetModuleData.I have a feeling that to view changes to the grid, a PostBack might be required, but I've removed all DataBinding to an If Not IsPostBack Then block because the alternative caused problems with the DropDownList whose selection is used as a reference to populate the grid (ddlModules selected the Module whose Questions will display in the grid).
I add a row to the DataSet using the following code: Dim NewRow as DataRow NewRow = gds.Tables("TitleDataSet").NewRow NewRow("Title") = txtTitle.Text NewRow("Local_number") = nubLocalnumber.Value NewRow("Number_suffix") = txtNumberSuffix.Text etc.
This code executes without errors but the bound DataGridView remains unchanged (without including the new row). Obviously I am doing something wrong or I am omitting a vital command. What do I need to do in order to make the new row appear in the DataGridView? I did not choose to bind the DataGridView directly to the database table because the database is selected by the user at execution time. Instead I bound the DataGridView to the DataSet. I included the command:L dgvTitle.AllowUserToAddrows = True but that did not have any effect.
Solved. Was missing the final command:L gds.Tables("TitleDataSet").Rows.Add(NewRow)
How can I assign a value to a message box for when the default value displayed in the text box is unchanged. ie. If my default value is 17 and the user clicks ok without retyping a number, the Input value displayed in a textbox will be 0.
Currently I have:
Public Class Form1 Dim MyValue As Double Private Sub But_EnterInput_Click(sender As System.Object, e As System.EventArgs) Handles But_EnterInput.Click MyValue = CDbl(InputBox("Input a value", "Data Input", "17", 200, 400))
[code]....
This works however if the user types 17, the textbox will read 0. not what i want.
i am using MS ACCESS DATABASE for data processing in vb.net, so i need to change the "connection string" while re-compile in another machines ,so i want to make connection string as stable(unchanged for all environment)
I'm selecting value from my database, passing it to datatable then giving DataGridView.DataSource value of datatable.The thing is that in those rows i'm also selecting some dates and problem is that my default date in database is '1900-01-01 00:00:00' because i use "smalldatetime". And what i want is this...when I find default value in database i want to show it like an empty string, like i said...because date is in smalldatetime format i can't do this in SQL query so i wonder how can I change this in DataTable or even better in DataGridView...of course, in code?
I was wondering if there is a way to change the Fill command text of a datatable before issuing it.I need this because the table I am opening has over 15 thousand rows and it hangs for a while in the network when filling the table. So I would like to tell it what to SELECT instead of getting the whole table and then applying a filter.If there's a way of doing that without changing the fill command, it will also work for me.
I'm retooling an app, and condensing my queries down to one, but to do so, I would like to move the columns for better presentation. I am reporting on errors for particlular equipment, and the user may want to get equipment by errors or errors by equipment. Is there any way to change column order?
I'm pulling data from my DB, adding it to a DataTable and binding that DataTable to my DataGridView. Before I bind the data, I need to change/remove some data. When I loop through the rows and use a Select Case, just for this column, it doesn't work. But if I use an If, it works fine. [Code] In the example above, the "Pass_Flag" row works just fine, but the "FailureCD" does not. But after the Select, with the If statement, it works. In the example, I'm casting the row as a string first and then an integer. I tried casting to an integer in the select case and it doesn't work either.
I created a RDCL in the designer. I would like the User to Determine what is shown in the Report. How can I change the query at runtime? (ex. changing the customer Name)
This is the query that I have in the properties:
SELECT [Date], Address, Customer, Orders FROM Report_qry WHERE (Customer= 'JohnDoe')
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?
I 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.
I'm using vb.net 2010.I have a DataSet with a Table and data. MyDataSet1 which contains Table1 I want to create another table that is the same as the Table1 but without data, but it should have the columns, etc.
Now, I want to place the rows from foundrows into an empty data table.I did what I thought was the obvious but that only returns a bunch of rows with no data
