Validating And Storing Selections From A Dataset Bound Combobox?

Mar 21, 2011

I have a combobox that is bound to a dataset.The dataset has 3 columns of data.at any given time there could NOT be any data in the dataset.When someone selects an item from the box I want to store data from 2 of the columns of the row they selected.I do the 'store' in the selectedindexchanged event.so currently I am assigning each column/row value to a property from a datarowview i get from combobox.selecteditem.

Code:dim column1 = drv.row.item(0).tostringdim column2 = drv.row.item(1).tostring

But I am getting NullReference exceptions all over the place when there is not data.So i have to wrap it all in a try catch and assign nothing to the properties when the Null exception fires.I want to also validate that there is a selection made. There must be a selection made if there is no data in the DS fill it.I do this in the combobox validate event.It just seems like there is a better way to check for no data coming from the combobox.I wish there was a way to do some sort of .count on the datarowview you get back from the combobox.selecteditem but anything i have found also gives a null ref exception if used.Also what is used to programmaticly change the selected item?.selecteditem.selectedtext.selectedindex.selectedvalue?

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Validating And Storing Selections From A Dataset Bound Combobox

Oct 20, 2009

I have a combobox that is bound to a dataset. The dataset has 3 columns of data. at any given time there could NOT be any data in the dataset.

When someone selects an item from the box I want to store data from 2 of the columns of the row they selected.I do the 'store' in the selectedindexchanged event.

so currently I am assigning each column/row value to a property from a datarowview i get from combobox.selecteditem.

Code:dim column1 = drv.row.item(0).tostringdim column2 = drv.row.item(1).tostring

But I am getting NullReference exceptions all over the place when there is not data.So i have to wrap it all in a try catch and assign nothing to the properties when the Null exception fires.

I want to also validate that there is a selection made. There must be a selection made if there is no data in the DS fill it.I do this in the combobox validate event.

It just seems like there is a better way to check for no data coming from the combobox.

I wish there was a way to do some sort of .count on the datarowview you get back from the combobox.selecteditem but anything i have found also gives a null ref exception if used.

Also what is used to programmaticly change the selected item?

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Get The Value From A Combobox When Have It Bound To A Dataset?

Jan 28, 2009

I'm using vb.net in vstudio 2005. how do I get the value from a combobox when I have it bound to a dataset?

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Dataset Doesn't Return The Selections?

Aug 17, 2010

im trying to get a selected time and my dataset doesn't return the selections what am i doing wrong in this statement

dim startindex as integer= 0
dim endindex as integer= 0
for each regel as datarow in my dataset.tables("Bookingen").rows

[Code].....

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Validating Datagrid Value Against Dataset Result?

Dec 20, 2011

I'm trying to validate the contents of a datagrid cell against the values in a Dataset:

VB

Private Sub dgOperator_CellValidating(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellValidatingEventArgs) Handles dgOperator.CellValidating

[Code]....

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Get Dataset From A Grid Which Has Already Bound To A Dataset?

Jan 11, 2012

I have a datagrid which is already bound to a dataset, I need to get this dataset,make changes on some data, then rebind the datagrid with the modified dataset.
here's my code

[Code]...

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Storing Dataset Into Dictionary?

Oct 14, 2011

this is the dataset:

[Code]...

however when i run the below, i got an error:

[Code]...

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Add New Row Into Dataset Via Bound Textbox?

Nov 27, 2011

i have 3 textbox and 1 listbox bound to the same datatable. when i insert new row to the datatable, there are 2 rows affacted in datatable, one row in datatable is replaced by the newly added row, and this new row is also insert into the end of datatable, while this modified datatable is updated into the database, only the inserted row is updated, the other modified row did not affacted in database.

here is my code:

Private Sub Form1_Load(ByVal
sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim DA As MySqlDataAdapter

[code]....

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Datagridview That Is Bound To A Dataset?

Apr 9, 2012

Okay so I have a datagridview that is bound to a dataset. I have a column called type is a string char of either C, R, A, or V. The problem is that I want to sort the datagridview rows using that column and do so in the order I just gave so I want rows with C on top and then R and then A and then V. Because these aren't alphabetical, how could I sort the items this way? I did look into the icomparer, but really wasn't able to figure out how that works.

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Change Path Of Bound Dataset?

Jan 7, 2012

I built my programs in VB 2010 using a temporary dataset on my computer.I am not ready to have them address the dataset on the server, but when I call up the dataset to change the path, the full path is light gray and I can not change it.If I delete the dataset, it will ruin all of the forms that automatically populate from the dataset. Is there an easy way to change the full path of a dataset?

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Clearing Datagrid Or The Dataset Bound To It?

Feb 15, 2012

I am binding a dataset (dsTest) with a table called "TempResult" to a datagrid (DatagridView1).The purpose of the datagrid is to display test labels (set elsewhere in the software) and to allow the user to enter results into an empty column titled results.To achieve this I've filled the dataset with the required test labels then added a column called "Result" with a default value of 0.00.The user can enter numbers into the "Result" column on the grid then click a button "ADD" to update the changes to the datatset,When I first open the form the datagrid shows the correct information and any changes made to the Result column are updated correctly - all is well.

Private Sub Add_Results()
Dim ResultColumn As DataColumn
Dim Rows As Integer
Dim i As Integer

[code]....

If I close the form and open it up again (i.e. the user wants to add more results) the datagrid shows the results entered the last time the form was use and any changes made to the grid are not updated and the form won't work again until the software is reloaded.

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Dataset, Bound Controls, Add New Row Error?

Jun 15, 2010

I don't normally use strongly typed datasets, but I am maintaining an existing application that uses them.This application has a form to edit rows in detail view, so we have the navigator toolstrip with nav buttons on top, including one to add a new row.When this button is clicked, I need to update one of the bound text boxes with a value from the underlyingThe field in question is defined as nvarchar 25 It's almost always integers in this field, but one row has a string.In the dataset, I have a table adapter to go get the max value + 1 where the field is numeric, like this:

SELECT internal_num = CAST(MAX(internal_num) + 1 AS NVARCHAR(25))
FROM dbo.invoice_log
WHERE ISNUMERIC(internal_num) = 1

[code].....

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Fill Bound DataSet In Backgroundworker?

Jul 10, 2010

I've added a Data Source to my project and a table from that Database (SQL 2005)

It is a rather large table and takes a LONG time to load the form. I was thinking of loading the auto-generated "Fill" statement in a Backgroundworker, but it doesn't seem to be doing anything. I have the Fill statement in the DoWork event, but it never "finishes" it seems. My BindingNavigator stays at 0.

I looked at jmc's sig link and everywhere I look, it seems like I'm going to have to iterate one at a time, but how can I do this for a bound datasource?

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Keep The DGV Inside The Group Box When It Is Not Bound To A Dataset?

Aug 30, 2009

I have a DGV which I am laying out in code as it is unbound. The problem I have is when it is inside a group box, it moves outside the group box to the top of the form.

If the DGV is not enclosed in a group box it stays put. I have tried docking the DGV to the group box but that does not work. If I have a dataset bound to the DGV, then there are no problems.

How can I keep the DGV inside the group box when it is not bound to a dataset?

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Updating Dataset On Bound Forms?

Apr 11, 2011

I have added a SQL Server datasource through the wizard. I created my forms which were bound to the dataset. Is it possible to change the datasource and dataset names while updating the dataset the binding controls of the form?

For instance, Server 1 has DB1 and Server 2 has DB2 (DB1 & DB2 store the same information/tables). Is it possible to keep the forms and only update the binding information if I want the forms to use DB2?

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Bound Relations Between Tables In A Dataset To Datagridview?

Aug 6, 2010

How to bound this dataset to datagridview?

[Code]...

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Bound Untyped Dataset Search And Select

Sep 21, 2009

I have an untyped dataset which is programmatically bound to a form in vb.net 2008. The first record in the dataset is not necessarily the record the user selected to view. I need a way to, after the binding is done, move the dataset to that particular record. I have a currencymanger in play for use of displaying the current record of how many records. I think I need to do a search and find the row number of the select record and then use the CurrencyManager.postion to do this but have had no luck in 3 hours to locate anything I can use.

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DataGridView Unchanged After Adding Row To Bound DataSet

Jun 11, 2010

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)

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DataSet Bound To DGV - Failed To Enable Constraints

Jul 31, 2010

I keep getting this error message (see image). What's weird is it's coming from a "typed" dataset that is bound to a DataGridView and even though I get this message, the DGV still loads with all the data. I've bound this dataset to the DGV thru the designer. Here is the line of code that is erroring out:
Me.adpItemMaster.Fill(Me.JewelryDBDataSet18.tblItemMaster)
I checked the table and the primaryKey for the tblItemMaster is unique for each row.

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Filter On Dataset Clears All Bound Controls?

Feb 18, 2011

The following code works (rows are filtered by the select expression), but then all the controls in the datarepeater are empty. When set to .DefaultView all records return and all controls have their values.

Private Sub CheckBox_FilterApplied_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CheckBox_FilterApplied.CheckedChanged
If CheckBox_FilterApplied.Checked Then

[code].....

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Remove Row From DataSet If Bound Table Is Sorted?

Aug 31, 2010

I have a DataGridView that is bound to a DataSet and I allow someone to remove a row from the table and I remove the row from the set. My code looks like this:

ds.Tables(0).Rows(dgCourseList.SelectedRows(0).Index).Delete()

My problem I found is if the grid gets sorted the index of the rows no longer corresponds to the indexes in the DataSet. As a result the wrong rows get removed from the set.

Can I solve this problem with maybe having to sort the DataSet on some sort event of the DataGridView?

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Simple Control Bound To An XML Sourced Dataset?

Sep 8, 2009

I have an app that downloads from a networked SQL database to a dataset and also to an XML file on laptops. Laptop users will take their executable and the XML file which the local dataset will read.Although I can get gridviews etc to bind to that dataset syntax such as
"TextBox1.DataBindings.Add("Text", ds, "fname")"

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Storing A Value For Each ComboBox Item?

May 6, 2012

In lack of a Value property I planned to use Classes for storing Text and Value properties for my ComboBox items. So far I've succeeded.Here is my class:

Public Class clCombobox
Public cname As String
Public cvalue As Integer[code]......

It seems like this works so far. But how do I get data back. Like if I want the value of the selected CheckBox item? I tried using:

CType(cmbCombobox.SelectedItem, clCombobox).Value() Did not work.

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Select Items In Code In A Listbox Bound To A Dataset?

Feb 23, 2011

I have a list box that is bound to a datatable, which works fine. The question I have is this. I have a list of values in the form of a sqlDatareader that I want to use to select values in the list box, that is to say if the value from from the datareader matches the value member from the row in the listbox then select the row. I've come up with the following code, but can't find the syntax to utilize the SetSelected method.[code]...

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ComboBox On Bound DataGridView?

Aug 1, 2011

For example; I have a DataGridView bound to a MYSQL Database. There are two string columns "Name" and "Gender". I need to make the "Gender" column a ComboBox where they can select "Male" or "Female".

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Set Data Bound Combobox To A Value?

Apr 22, 2012

I have a data bound combo box which i want to open at a certain row in the table

i can't set the selectedvalue because it is databound

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VS 2008 How To Bound Combobox

Nov 10, 2010

I have a combobox2 this is bound to a datasource, which is an arraylist calledListItems.Everything is correct after the first For Next Statement - the listbox1Combobox1, and ComboBox2 all have 11 items. After the second for next loop, Listbox1 and ComboBox1 have 6 items, but ComboBox2 has 11 items, even though ListItems has only 6 items.

ListBox1.Items.Clear()
ComboBox1.Items.Clear()
ListItems.Clear()

[code].....

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Address Book Application Using Typed Dataset & Bound Controls?

May 29, 2010

I am writing a simple Address Book Application using Typed Dataset & Bound Controls. 1<sup>st</sup> Form for Entering Addresses 2<sup>nd</sup> Form for Adding New 'CITY'. To select a city for address I am using a data bound combo box which shows a list of Cities.

While entering with a address if user found the required City Name is not found in the Combo list, he opens a 2<sup>nd</sup> Form to Add a City name to database & returns to Form1.

Here the expected newly added city doesn't appear in the combo list, so I tried to Refill the underlying table with following code

[Code]...

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Dataset Bound Datagridview Not Showing Latest Data From Database

Jun 5, 2011

I 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]....

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Dataset Not Updating When Bound Text Fields Are Changed In Code?

Sep 1, 2009

I am having issues understanding why it is that a text box that has been bound to a dataset correctly updates that dataset when the text in the box is manually changed i.e. by changing it using the keyboard but the dataset does not recognise the change when I change it in code.Am I missing something obvious? The text is changed in code when the user clicks on a command button that copies the text from another textbox on the form to this textbox.

[Code]...

As i mentioned, manually it works fine but when I use the comman button to change the text it does not recognise that any changes have occured.

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