how the various elements that help you handle errors work together. Have tried several options and can't make head nor tail of it. The underlying table has two columns, an autoincrement integer and a text column with the following settings:
[Code]...
I am using the DataSet to test for data errors on a DataGridView (to give the user feedback before they save changes back to the database). RowChanging event has the code at the bottom and this manages error messages on the DGV via an ErrorProvider. I want to add something to this code that esnures there are no duplicate rows (it's a 2 column table and one of those is the autoincrement PK). However I cannot work out how to do this and since the column in the database is set to Indexed (No Duplicates) it will throw an Ole error if I don't handle it, I could manage it in a Try block around TableAdapter.Adapter.Update but would prefer not to add needless round trips to the DB when it really ought to be simple to do it in the code (and preferably in the DataSet, not the form).
I found the following code (Forum Post) and try as I might I can't make it work since I can't get access to a DataTable within the RowChanging event that allows me to run DataTable.Rows.Find().
Dim expression as String
Dim matchingRow as DataRow
matchingRow = Mytable.Rows.Find(expression)
In my case:Mytable would be some kind of reference to the table / dataset etc.
'expression' would be e.Row.compclass.ToString
* a reference to the database table the form works with (bearing in mind that this code is in the DataSet not in the form). I've tried properties/methods of the DataSet itself; creating a new DataTable and linking it to the DataSet Table (or DB Table); creating
a new DataTable and loading it with the table contents - Searching MSDN and the forums hasn't popped anything up yet.I'm currently experimenting around this code:
Dim strCompClass As String = e.Row.compclass.ToString
strCompClass.Trim()
Dim foundRow As DataRow = ???.Rows.Find(strCompClass)
[code]....
This is the current code in the RowChanging event. The new code would be inserted after the last End If in the code below.
Private Sub ref_compclassDataTable_ref_compclassRowChanging(ByVal sender As System.Object, ByVal e As ref_compclassRowChangeEvent) Handles Me.ref_compclassRowChanging
If e.Row.HasErrors Then
[code]....
I have an ErrorProvider on a form with a DataGridView.The Binding Source for the DGV points at a single table in the DataSet (which hooks up to an underlying Access DB).The table has two columns:
1) Autoincrement PK
2) Text field, <=25 chars, unique, can't be Null or empty string
I test for string length (>0 and <=25) in the DataSet.Table.RowChanging event.If it's out of range then I use e.Row.SetColumnError, that passes the error to the ErrorProvider / DGV on the correct row and DataSet.HasErrors returns True. All good, no problems.
I test for uniqueness in the DataSet.Table.ColumnChanging event.If it's not unique I can set the error with either e.Row.SetColumnError or e.Row.RowError; Now it gets complicated since sometime this makes the ErrorProvider / DGV show the error and sometimes not, it depends on whether the DataSet keeps the Unique = True constraint of the underlying DB.
Why would I have the DataSet be False for Unique when the DB is True for same constraint? So that the user interaction with the form has the minimum of dialogue box based interuptions. I am trying to design a system whereby all issues / errors are reported
to the user as they interact with the form in a subtle way, allowing them to keep working but trapping errors before any attempt to Save from the DataSet to the DB.
So, if the DataSet keeps the unique constraint then when you insert the new (duplicate) row the DGV throws its DataError event, a default dialogue appears, behind which the DGV has the ErrorProvider icon on the correct row. However, since the DataError event
causes the problematic change to be rolled back, the new row is removed and the error disappears.
If I change the DataSet requirement to Unique = False, then SetColumnError does not cause an ErrorProvider icon to be shown and DataSet.HasErrors returns False. I can improve upon this slightly by using RowError, this causes DataSet.HasErrors to return True but the ErrorProvider icon still does not show.Further, when using Unique = True on the DataSet, and editing an existing row to be a duplicate of another, the behaviour is the same, DGV.DataError event, roll back of the change but the ErrorProvider icon remains, despite the row no longer being a duplicate and DataSet.HasErrors returns True. The text of the the ErrorProvider tooltip is the one from SetColumnError, not RowError.So, the behaviour of SetColumnError is affected by the state of the DataSet field Unique constraint?
Unique = True
SetColumnError affects the DGV / ErrorProvider and DataSet as expected.
(RowError behaviour unknown)
Unique = False
[code]....
What is the difference between ErrorProvider.Clear() and ErrorProvider.SetError(tBox,vbNullString)
Is there a preference for one or the other?
I have been reading up on this, but I can't get it to work for me. I am reading in comma delimited text into a three-column datagridview control. The third column is a combo box which only accepts certian values. If the data being imported into col 3 is not in the combo box list I get an error that tells me to handle the data error event.trying to capture that error and get rid of the default error message box. I am working with a Try/Catch statement, but it doesn't seem do anything.
Do Until fileReader.EndOfStream
stringLine = fileReader.ReadLine()
If Not stringLine.StartsWith("'") And Trim(stringLine) <> "" Then
[code].....
I cannot Unresolve a post.I have a datagridview control with a combo box. The user loads data from a file into the control. If there are errors (the element in the combo box column is not in the combo box list) I would like to:
1. capture the row in which the error occurred, and store it in code/memory
2. change the cell backround to red (this is not that important)
3. continue without a message at the time of the error
4. post a message with all of the errors after the load is complete
I am using the code staight out of the Microsoft example to try to figure how to do this, but it is not posting any messages when I load bad data, so I am not getting any smarter from the example.[code]
I'm trying to clear a DataTable and repopulate it, and the DataTable is bound to a DataGridView. Here's the code I'm executing:
vb.net
Using reader As MySqlDataReader = myCommand.ExecuteReader
SyncLock tableLock
running.Clear()
[Code]...
If you want to replace this standard messagebox, handle the DataError-expection
When debugging, there is no break in the code. The messagebox just pops up without showing me exaclty where the error is located.
I am using a DataGridView bound to a BindingSource which is itself bound to a List of objects. This all works well until I remove objects from the list. If I am scrolled down to the bottom of the DataGridView and then remove a bunch of items from the list it is bound to it generates a DataError exception because the length changed and the rows I am looking at no longer exist... I changed my code to handle that error, but now instead of popping up a message it SLOWLY erases the data in each of the newly invalid rows at the end of the table (I think each time it does one it generates a new DataError, which is why it is so slow).
How do I prevent this? I want to be able to dynamically (and programmatically) add and remove items from the table without the possibility of this error... I assumed this would be handled automatically as part of the data binding process but I guess not.
We would like to have 2 ErrorProviders for a DataGridView. The standard ErrorProvider and another WarningProvider with a different icon. Also is it possible to Left Justify the standard ErrorProvider icon in specific DataGridView cells?
View 1 Repliesfill a NEW DataSet's DataTable with data from a DataGridView? I am generating a data report that uses that "new DataSet." I need to go from a DataGridView to a DataSet because i need the person to be able to perhaps edit the information before its inserted into the report. my process to generate the report is...
- fill datagridview with advanced join sql
- allow user to edit datagrid if necessary
- put datagrids modified information in new dataset
- set report's databinding source to new dataset
- generate report...
i am trying to get data from the clipboard into dataset and view it on a datagridview using the code below. The problem is that every line after the first line starts with a character (like a small rectangle) but when i run a sperate loop to view each character i do not find any unexpected asc code.
'this is the text in the clipboard
this is
a test
to get
[code]...
I am working in vb.net and i have a simple requirement. I have added a MDB file to a dataset and it contains 21 tables. I have a datagridview and a combobox on my form. I was able to get the combobox populated with the table names available in the dataset by iterating through dataset.tables. Now i want to add the feature where the user can select the table name from the combo and then it should populate the contents of that table. I tried the following Code
[Code]....
I wrote small program which is able to open database using OpenFileDialog, then I added binding navigator (so I can navigate and make changes in my data set) and now I would like to SAVE data which I see in datagridview AS NEW FILE... I have a question: How to save data (and changes) from datagridview using SaveFileDialog?[code]
View 5 RepliesI am creating one application visual basic and sqlce.I have two forms name Form1 and Form2.
I used Form1 to add data to database using OLeDb command and used Form2 to show data in datagridview by using dataset[code]....
I'm using VB.net 2005 and sql server 2000 i'm fetching the data into datagridview, but datagridview has several datasource depending on the "select case " Now can i export the data from datagridview without referring to dataset/datatable?
View 1 RepliesI have a problem with one of my projects that has only just started occuring this morning.I am using VS 2010.I get errors on every form that has a VS generated dataset, similar to;
me.<dataset> = new <namespace>.<dataset>()
and
with events <dataset> as <namespace>.<tableadapters>.<tableadapter>
[code].....
This is how I update a table using DataAdapter and DataSet in VB using SQL Server[code]...
I know that the Fill method does not make sense in case of an INSERT statement, but I am new to this technology and the above statement does the job and updates the table w/o problems. My question is this: If there was an error (say a duplicate key error) how would I know this in my application? Should I be putting the above code in a try/catch block?
Also, if there is a "proper" method for running INSERT statements using a DataAdapter/DataSet combination that does not use the Fill method, please indicate that as well.
I am experiencing something very bizarre when I execute the Fill method of my adapter. I've been running this query for months and all of the sudden this is happening after I installed SP1 for Visual Studio 2008. For some reason several DataRows in 2 of the 3 tables within my DataSet have errors in them when I view them in debug mode using the DataSet Visualizer. Here is a picture of what I'm talking about
It does this to random rows. If I execute the Fill method the first time, rows (5-10) will have these errors. If I execute the Fill method again rows 12-23 are affected and so on. I have no idea what is happening here.
This is effected my DataGridViews, because they don't display any rows, because of the erros. I should also note that when I run the lines of code below in the Immediate Window it says the DataSet doesn't have errors.
?Me.ds.Tables("Current").HasErrors
False
?Me.ds.HasErrors
False
I setup a strongly typed dataset using the DatasetDesigner in VB2010. I am using the TableAdapter.Insert method to add data to an Access table. Before the data is inserted I need to validate the data using the DataTable RowChanging event.
How can I get the DataTable RowChanging event to fire when using the TableAdapter.Insert method?
Here is an excerpt of code I have so far:
When the Insert method runs, it does not fire the datatable RowChanging or NewRow events.
Imports System.IO
Imports System.Data.OleDb
Imports System.Data
[Code]....
I am using VB 2010 Express to create a windows forms application with an unbound DataGridView. The DataGridView has multible columns, two of which are ComboBox Columns. I would like to make the borders of the cells be bold when selected as some type of indication to which cell is the current cell. It is possible that I overlooked something completly but I could not seem to find a property that would allow this to happen.
My solution was to create a custom class which inherits from the appropriate DataGridViewCell type (e.g. DataGridViewTextBoxCell, etc..), in that class I override the Paint sub. There I check the selected property and draw a rectangle using the cell bounds.
This works with every type except the DataGridViewComboBoxCell. On the columns of this type I receive an ArgumentException on the call to the Paint Sub. Even if I just have an empty class that only inherits from the DataGridViewComboBoxCell.
Again, it is quite possible that I have overlooked somthing and am making the a lot more complicated than it needs to be.
1. I can check a DataSet for errors with DataSet.HasErrors and I wonder how to check the same thing for a DataGridView.
2. Coming from MS Access I am not used to batch editing a dataset via a datagridview for instance. Think of a multi user Windows forms application / SQL Server setup. So I wonder if it's ok to just save the data after a row has changed, edited or deleted and not wait till all modification are done and then do a batch update?
I'm loading a dgv with dates from a MySql table. Adding also works fine. No issues there, but when I try to change the date via the datagridview the following exception is thrown:
Quote:
System.FormatException: Invalid cast from 'System.String' to 'MySql.Data.Types.MySqlDateTime'. ---> System.InvalidCastException: Invalid cast from
[code].....
I have tried everything I can to get beyond this error which shows below as <<<<< error here. It is trying to fill a dataset from a data adapter. If I change the SELECT statement to just SELECT * FROM xTable I get the correct number of records in each table. But anytime I try with a more complex statement I get the error message shown below which indicates System.Data.Common.DbDataAdapter.Fill(DataSet dataSet. I've completely erased all data and entered a new set of test data so I know there is no problem with relationships. Each table has primary key which is foreign key in other table. IS there something wrong with the Imports section: Imports System
[Code]...
i am trying to copy data from a standard Dataset to a Type Dataset (XSD) of same table structure. i want to use Automapper to do that one. So how can i do that using automapper?
View 1 RepliesI have two Datagrids, One grid has all the customers garments on it with style number and contact length. The other grid has the users who have garment issued to them. the style number is in both grids. I need to loop through the users grid and say if the contract number is 1 from the first grid then the contract date on the second grid will be todays date + 365 days (year contract) I have looked at using a stored procedure and also a for each command but I am just getting stuck with it all. [Code]
View 1 RepliesI would like to ask how to clear the ErrorProvider in VB.net 2003? ErrorProvider.Clear() isn't working in vb2003. i know it's very simple
View 2 RepliesI doing something really simple on vb studio 2008 express, i added a table from a datasource directly to the windows form and created a datagridview the table has no data yet, it has a primary key id int, and some columns some of then allow nulls, i added the entire table with the common steps and when clicking in the add button of the bindingnavigator twice i get the not nullable column is allowed exception but i dont know where does this exception ocurrs beacuse it breaks with no code line another thing is that i clic on the delete button when theres no data and i get an invalid operation exception again with no code line break why is this configured that way? am i missing any step in order to avoid this exceptions?, i tried to handle the dataerror event of the datagrid and set throwexception to false but some errors are not trapped like the ones at the top of this?
View 2 RepliesProblem: Calling a method which uses a cell's value from a DataBound DataGridView. Works as desired without adding an image column.When I add the image column, the method attempts to use the value from column 1 instead of column 2, as the code in the 2nd method below ("findSign") states:
vb
Private Sub getAtmTOF()
Try
[code].....
I'm having troubles with my errorprovider and i already found out what the problem is - the textbox is bounded twice (Display Member and Value have different binding sources) and so the errorprovider is showing the same error twice. If i remove one binding source,everything is fine.Any suggestions?Oh - I'm validating the columns in my DataSet.vb with DataTable_ColumnChanged Sub with table.setColumnError().Another problem ->I have a field (decimal) in my dataset that is optional (can be null). But if the user writes something in and then deletes it so that the textbox is empty, the errorprovider is showing the error "Input string was not in a correct format."
View 1 RepliesI have put my business logic in a partial class as suggested in best practices. One of the conditions is that one of four fields of a row has have a value. Setting the errorprovider has no problems when creating a new row in the new row event. All the textboxes in the form show the error condition.
Dim ErrorString As String = "A value is needed for at least one of the " & vbCrLf & "Gallon, Fuel, Oil, or Misc fields"
e.Row.SetColumnError("Gallons", ErrorString)[code]....
The logic that sets them back to a no error condition though only sets the currently focused control in the form to no error. When the error is corrected.
MyFuelRow.SetColumnError("Gallons", "")
MyFuelRow.SetColumnError("FuelCost", "")[code]....
How can you reset multiple column errors at once?
