Problem with combobox and databound datagridview

Question

Hi

I have a datagridview that is databound to a table via a bindingsource and a DataGridViewComboBox column that is bound to a second table (both in the same dataset). I am dynamically adding the column to the grid. 

Dim viewcol As New DataGridViewComboBoxColumnviewcol.DataSource = _dsEquivalents.Tables(1)
viewcol.DataPropertyName = "ViewName"
viewcol.ValueMember = "ViewTable"
viewcol.DisplayMember = "ViewTable"
viewcol.HeaderText = "View Name"
viewcol.AutoComplete = False
dgvEqu.Columns.Add(viewcol)

BindingSource1.DataSource = m_dsEquivalents
BindingSource1.DataMember = m_dsEquivalents.Tables(0).TableName

The table bound to the grid contains values that are not in the table bound to the combo. This causes an Dataerror which I trap but the value still doesnt display in the grid. Do I need to do an ovverride? I would also like to be able to type values into the cell that are not in the combobox is this possible?
 

Answer 1

The DataGridView raises a DataError when the value is not in the ComboBox's list.  To display the value, you must add the value to the ComboBox.  The other option is to create your own combobox column.

There must not be a foreign key relationship between your two tables, or else you wouldn't be having this problem.  How were you going to have users enter data not in the combobox?  It seems like you are looking for the ComboBoxStyle.DropDownList behaviour in DataGridViewComboBoxColumn.   What follows is an example of how to accomplish this.

The ComboBox used by the DataGridViewComboBoxColumn has a DropDownStyle property set to ComboBoxStyle.DropDownList, but DataGridViewComboBoxColumn does not expose this property, so out-of-box there is no way to type text into a combobox column.  You can change this by handling the EditingControlShowing event, and setting the DropDownStyle:

void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e) { if (e.Control.GetType() == typeof(DataGridViewComboBoxEditingControl)) { DataGridViewComboBoxEditingControl cbo = e.Control as DataGridViewComboBoxEditingControl; cbo.DropDownStyle = ComboBoxStyle.DropDown; cbo.Validating += new CancelEventHandler(cbo_Validating); } }

In this example, all ComboBox columns will have the DropDownStyle property set to DropDown.  In addition, handle validating to add user-typed items to the list.

void cbo_Validating(object sender, CancelEventArgs e) { DataGridViewComboBoxEditingControl cbo = sender as DataGridViewComboBoxEditingControl; DataGridView grid = cbo.EditingControlDataGridView; object value = cbo.Text; // Add value to list if not there if (cbo.Items.IndexOf(value) == -1) { DataGridViewComboBoxColumn cboCol = grid.Columns[grid.CurrentCell.ColumnIndex] as DataGridViewComboBoxColumn; // Must add to both the current combobox as well as the template, to avoid duplicate entries... cbo.Items.Add(value); cboCol.Items.Add(value); grid.CurrentCell.Value = value; } }

Answer 2

Hi Durstin,
                In your post you said:
>    "The other option is to create your own combobox column."

Any chance you could give me a quick run through on how to do this? I presume it would mean inheriting from DataGridViewComboBoxColumn which in turn would mean inheriting from DataGridViewComboBoxCell in order to get access to the editing control. What method in DataGridViewComboBoxCell would I have to override in order to ensure any data which is not in the combo box's datasource is still drawn?

I hope this makes sense!, if not I will try and explain it better.

Thanks,
Cathal.

Answer 3

couple of things:

1) seems that with every EditingControlShowing event an Additional handler is added and they build up.  Shouldn't the tail end of cbo_Validating have:
cbo.Validating -= new CancelEventHandler(cbo_Validating);
added so that cbo_Validating only executes once per EditingControlShowing event?
when i add a trace to check the number of times cbo_Validating fires the number keeps getting higher ... maybe i implemented it different than you...

2) intermittantly I'm still getting the data error.  not every time, but enough that I notice. And when I'm getting the error it seems that the data_error event is raised before the cbo.Validating event.  I'm starting to think about adding the item in .cellValidating as it executes before .DataError event

what do you think?

/gabe

Answer 4

hi,
i have the same situation like in the first post. I tryed to bound the combobox via
smart tag and manually in the formattingcell event. I bounded it to a dataset,datatable,dataview,arraylist. it always raises an dataerror.(wrong value)

please give me an example how to bind the box to one column of my datatable.

thanx

Answer 5

http://www.windowsforms.net/Samples/Go%20To%20Market/DataGridView/DataGridView%20FAQ.doc

seemed to answer the vast majority of the problems i had.  if that doesn't lead you to the solution repost and i'll put together a sample

gabe

Answer 6

Thanks  again.

Answer 7

hi,

in my program i have used one combobox . when i desing this combobox that time this is ok but now this combo is look transperent how it happened ? when i click on combo then it look like combo with item list but at first time when programe started it will like textbox with out border. i put another combo but it is like old one . this effect is show in this project only  if i working another project then combo is like good. if you say then i send you this splash screen with this combo.

please give me solutional for this problem.

 

raju

 

 

 

Answer 8

A thought for you Raju.

Check to see if the DisplayStyle for the column is DropDownButton
and the DisplayStyleForCurrentCellOnly is false.

Answer 9

I pieced together helpful code from this thread and other sources, translated them to VB.NET and enhanced it to work for ALL comboboxes in the DataGridView.  These routines should make the comboboxes editable, i.e., allow users to enter new values.  (I also included commented out code that limits it to a specific combobox.) 

VB programmers should be able to copy and paste this code and just change "MyDataGridView" to the name of their DataGridView.  (If you uncomment the code that uses "MyDataGridViewComboBox", you will need to change that to the name of your combobox.)

This assumes that the combobox list is not bound to a datasource, but filled in the Form_Load event.  This needs to be done for each combobox in the DataGridView.  Here is a sample:

'TODO: This line of code loads data into the 'MyDataSet.MyList' table. You can move, or remove it, as needed.

Me.MyTableAdapter.Fill(Me.MyDataSet.MyList)

MyDataGridViewComboBox.Items.Clear()  'This probably isn't necessary if done in the Load.

'fill combobox

Dim row As DataRow

For Each row In Me.MyDataSet.MyList

MyDataGridViewComboBox.Items.Add(row.Item(0))

Next

VB programmers should be able to copy and paste the rest of this code and just change "MyDataGridView" to the name of their DataGridView.  (If you uncomment the code that uses "MyDataGridViewComboBox", you will need to change that to the name of your combobox.)

Private Sub MyDataGridView_EditingControlShowing(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles MyDataGridView.EditingControlShowing

'Allow user to enter new values for ALL DataGridViewComboBox controls in the DataGridView

If (TypeOf e.Control Is DataGridViewComboBoxEditingControl) Then

Dim cmb As DataGridViewComboBoxEditingControl = CType(e.Control, DataGridViewComboBoxEditingControl)

If Not cmb Is Nothing Then

cmb.DropDownStyle = ComboBoxStyle.DropDown

End If 

End If

'Following Works for a specific combobox ///////////

'If MyDataGridView.CurrentCellAddress.X = MyDataGridViewComboBox.DisplayIndex Then

' Dim cmb As ComboBox = CType(e.Control, ComboBox)

' If Not cmb Is Nothing Then

' cmb.DropDownStyle = ComboBoxStyle.DropDown

' End If

'End If

End Sub

 

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

'Allow user to enter new values for all DataGridViewComboBox controls in the DataGridView

If (TypeOf CType(sender, DataGridView).EditingControl Is DataGridViewComboBoxEditingControl) Then

Dim cmb As DataGridViewComboBoxEditingControl = CType(CType(sender, DataGridView).EditingControl, DataGridViewComboBoxEditingControl)

If Not cmb Is Nothing Then

Dim grid As DataGridView = cmb.EditingControlDataGridView

Dim value As Object = cmb.Text

'// Add value to list if not there

If cmb.Items.IndexOf(value) = -1 Then

'// Must add to both the current combobox as well as the template, to avoid duplicate entries...

cmb.Items.Add(value)

Dim cmbCol As DataGridViewComboBoxColumn = CType(grid.Columns(grid.CurrentCell.ColumnIndex), DataGridViewComboBoxColumn)

If Not cmbCol Is Nothing Then

cmbCol.Items.Add(value)

End If

End If

grid.CurrentCell.Value = value

End If

End If

''Following Works for a specific combobox ///////////

'If e.ColumnIndex = MyDataGridView.Columns("DataGridViewComboBoxColSize").Index Then 'CType(sender, DataGridView).CurrentCell.ColumnIndex

' 'Dim cmb As ComboBox = CType(e.Control, ComboBox)

' Dim cmb As DataGridViewComboBoxEditingControl = CType(CType(sender, DataGridView).EditingControl, DataGridViewComboBoxEditingControl)

' If Not cmb Is Nothing Then

' Dim grid As DataGridView = cmb.EditingControlDataGridView

' Dim value As Object = cmb.Text

' '// Add value to list if not there

' If cmb.Items.IndexOf(value) = -1 Then

' '// Must add to both the current combobox as well as the template, to avoid duplicate entries...

' cmb.Items.Add(value)

' Dim cmbCol As DataGridViewComboBoxColumn = CType(grid.Columns(grid.CurrentCell.ColumnIndex), DataGridViewComboBoxColumn)

' If Not cmbCol Is Nothing Then

' cmbCol.Items.Add(value)

' End If

' grid.CurrentCell.Value = value

' End If

' End If

'End If

''//////////

End Sub

 

Private Sub MyDataGridView_DataError(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewDataErrorEventArgs) Handles MyDataGridView.DataError

'I don't know if this is really necessary.

If e.Exception.Message = "DataGridViewComboBoxCell value is not valid." Then

e.Cancel = True

End If

End Sub

Answer 10

My reply is to the origianl post and also that which explians the cause of the error as a value not in the list of items in the combobox column.

First I have the same problem as originally stated. I'm convinced that the combobox column property DataPropertyName is not set to something valid - in fact the DataSource for the box seems to supply info from only one table - it is after set to a single DataTable object.

As for values not being in the dropdownlist, I agree its a problem, but in a parent/chaild table, the re will be FK's in the parent table that are NULL. This should not cause an error. It certainly doesn't in the normal Combobox control. I have both on a single form and the normal combobox works fine from the same two tables all because it can be bound to both tables through data bindings. The combobox column doesn't have that ability.

Answer 11

Hi,

I have copied this code but I get this error:

"No se puede modificar la colección Items cuando está establecida la propiedad DataSource."

in

cmb.Items.Add(value)

I fill the comboboxcolumn from a database and I belive that this is the problem. How can I solve it?


Thanks

Answer 12

First, I can't read much else but English, so I don't understand your question.

Second...In many other posts of mine and others' its become clear that the DataGridView Combobox control is incomplete. It needs the capability to bind to two tables in a dataset. The normal combobox control has this ability through its databinding collection. The current DGV Combobox gives all of us roughly the same errors for very much the same reasons.

Answer 13

Hi mafc,

I'm guessing your problem is you have bound the DataSource property.  Instead, set DataSource to "none" and fill the combo's Items collection in the Form_Load event.  Here is sample code from my previous post in this thread to do this:

Me.MyTableAdapter.Fill(Me.MyDataSet.MyList)

MyDataGridViewComboBox.Items.Clear()  'This probably isn't necessary if done in the Load.

'fill combobox

Dim row As DataRow

For Each row In Me.MyDataSet.MyList

MyDataGridViewComboBox.Items.Add(row.Item(0))

Next

Hope that helps!

Answer 14

Yes this is my problem, but I don't know how to use your example in my code.  My code is this :

            dim column_combo As DataGridViewComboBoxColumn = New DataGridViewComboBoxColumn()
       .....

            SQL = "select CANT_NOMBRE from T_CANTIDADES"

            Dim dbDataSet_Cantidades As New Data.DataSet
            Dim tabla_Cantidades As New DataTable

            Try
                dbDataSet_Cantidades.Clear()

                dbDataAdapter = New FirebirdSql.Data.FirebirdClient.FbDataAdapter(SQL, FbConnection)
                dbDataAdapter.Fill(dbDataSet_Cantidades)

                tabla_Cantidades = dbDataSet_Cantidades.Tables(0)

            Catch ex As Exception ' catches any error

                MsgBox("Ha fallado al rellenar la columna cantidad")
            Finally
            End Try

            With column_combo

                .DataSource = tabla_Cantidades
                .ValueMember = "CANT_NOMBRE"
                .DisplayMember = .ValueMember
                .......
                .DataPropertyName = "CANTIDAD"
                .HeaderText = "CANTIDAD"
                .HeaderCell.Value = "CANTIDAD"

            End With

            Me.DGV_Recetas.Columns.Add(column_combo)

Can I incorporate your code in the mine.

Thanks

Answer 15

 

 Hi mafc,

Try this code (notice I took out ".DataSource = tabla_Cantidades" and replaced it with filling the items collection):

            dim column_combo As DataGridViewComboBoxColumn = New DataGridViewComboBoxColumn()
       .....

            SQL = "select CANT_NOMBRE from T_CANTIDADES"

            Dim dbDataSet_Cantidades As New Data.DataSet 

            Try
                dbDataSet_Cantidades.Clear()

                dbDataAdapter = New FirebirdSql.Data.FirebirdClient.FbDataAdapter(SQL, FbConnection)
                dbDataAdapter.Fill(dbDataSet_Cantidades)

            Catch ex As Exception ' catches any error

                MsgBox("Ha fallado al rellenar la columna cantidad")
            Finally
            End Try

            With column_combo

             Dim row As DataRow

                 For Each row In dbDataSet_Cantidades

                       .Items.Add(row.Item(0))

                 Next

                .......
                .DataPropertyName = "CANTIDAD"
                .HeaderText = "CANTIDAD"
                .HeaderCell.Value = "CANTIDAD"

            End With

            Me.DGV_Recetas.Columns.Add(column_combo)

Answer 16

Thank you mcassoc for your help. I have followed your advice and It works with a little change. I have marked in red.

Dim row As DataRow
For Each row In tabla_Cantidades.Select
.Items.Add(row.Item(0))
Next

Now, I can edit the comboboxcolumn but the value that I write in the combobox disapper when I change to other cell. Which is the problem?

Thanks

Answer 17

Hi mafc,

Glad to help.  I know it took me quite awhile to figure this out and I appreciated help from others.

Here are some questions to try to narrow down the problem:

Do you have my code from my 8/16/06 post in these three subs?

DGV_Recetas_EditingControlShowing

DGV_Recetas_CellValidating

DGV_Recetas_DataError

Is the datatype the same for your "CANTIDAD" field that you use for the DataPropertyName and the "CANT_NOMBRE" in the T_CANTIDADES table?

Do other fields in the grid get saved properly?

Is the value you typed getting added to the dropdown list?

Answer 18

Hi all,

  My case is like this, I have a DataGridView where the first column is a combo box, the items in the combo box are added from a dictionary

foreach (KeyValuePair<string, long> key in dictionary)
{
    tmpCol.Items.Add(key.Key);
}

This code is in the constructor of the form, and I have done everything as stated by durstin and mcassoc, I can now edit the combo box etc.

But now i have two problems:
1. After I selected an item and lose the focus of the cell, i got back to the combo box, the items in the combo box are doubled....

say like i have A, B, C in the combo box and I chose B, lose the control and i go back, the combo box will have A, B, C, A, B, C... I didn't implement to add the items to code else where but in the constructor only, any clue how could this happen?

2. I also have the same problem as mafc, I can edit the comboboxcolumn but the value that I write in the combobox disapper when I change to other cell, I solve this by implementing CellLeave event, I cleared the items in the comboboxcolumn and I add the items from the dictionary back into it again, and then

DataGridView.CurrentCell.Value = theTextWasTypedInByTheUser;

this is ok if I have few items, but if I have many items it will be very slow, any one has a clue on how to solve this also?

I am quite new to this stuff, Thank you very much

Answer 19

As you said to me the datatypes aren't equal. "CANTIDAD" is INTERGER and CANT_NOMBRE is VARCHAR.

I have a column "CANTIDAD" that it will a number column (100, 500,...), but in the combo I want to have a varchar code (¼,½,¾). I want to give the oportunity of put ½ instead of 500. Is this posible?

Thanks

Answer 20

I change the sql and I have the same type in both. The two are integer and I have the same problem.

Answer 21

I used mcassoc's code from the previous page converted to C# and have it working except for one very annoying problem.  I go through the cells editing the values, but then if I go back to a cell and click on it, it goes into edit mode as expected with all of the text selected, but if I click the down arrow, the dropdown opens, then immediately closes.  No matter what I do, I cannot get the dropdown to stay open.

I can still edit the value in the cell by typing in a new value or by using the cursor keys to scroll through available values, but the dropdown doesn't work.

Does anybody else have this problem or have any idea what I might have done wrong?  I have been trying everything I can think of, so any help would really be appreciated.  Thanks.

Answer 22

Rob,

I'm sorry I don't have a solution for you.  I don't have that problem in my VB forms.

mcassoc

Answer 23

mafc,

Text will not display in the cell after you leave it if it has not been added to the combobox dropdown list properly.  Please see my code in MyDataGridView_CellValidating in my 8/16/06 post to see how to do this.

I'm sorry I didn't respond months ago.  Hopefully, you figured it out.

mcassoc

Answer 24

Paul,

As I mentioned in my post  to mafc, text will not display in the cell after you leave it if it has not been added to the combobox dropdown list properly.  Please see my code in MyDataGridView_CellValidating in my 8/16/06 post to see how to do this.  Make sure you are adding new values to the current combobox and the template.  This will help prevent some duplicates, but I don't understand why your entire list is getting duplicated if the only "Add" code is in the constructor of the form (and individual items that the user adds in CellValidating). 

I'm sorry I didn't respond months ago.  Hopefully, you figured it out.

mcassoc

Answer 25

I pieced together helpful code from this thread and other sources, translated them to VB.NET and enhanced it to work for ALL comboboxes in the DataGridView.  These routines should make the comboboxes editable, i.e., allow users to enter new values.  (I also included commented out code that limits it to a specific combobox.) 

VB programmers should be able to copy and paste this code and just change "MyDataGridView" to the name of their DataGridView.  (If you uncomment the code that uses "MyDataGridViewComboBox", you will need to change that to the name of your combobox.)

This assumes that the combobox list is not bound to a datasource, but filled in the Form_Load event.  This needs to be done for each combobox in the DataGridView.  Here is a sample:

'TODO: This line of code loads data into the 'MyDataSet.MyList' table. You can move, or remove it, as needed.

Me.MyTableAdapter.Fill(Me.MyDataSet.MyList)

MyDataGridViewComboBox.Items.Clear()  'This probably isn't necessary if done in the Load.

'fill combobox

Dim row As DataRow

For Each row In Me.MyDataSet.MyList

MyDataGridViewComboBox.Items.Add(row.Item(0))

Next

VB programmers should be able to copy and paste the rest of this code and just change "MyDataGridView" to the name of their DataGridView.  (If you uncomment the code that uses "MyDataGridViewComboBox", you will need to change that to the name of your combobox.)

Private Sub MyDataGridView_EditingControlShowing(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewEditingControlShowingEventArgs) Handles MyDataGridView.EditingControlShowing

'Allow user to enter new values for ALL DataGridViewComboBox controls in the DataGridView

If (TypeOf e.Control Is DataGridViewComboBoxEditingControl) Then

Dim cmb As DataGridViewComboBoxEditingControl = CType(e.Control, DataGridViewComboBoxEditingControl)

If Not cmb Is Nothing Then

cmb.DropDownStyle = ComboBoxStyle.DropDown

End If 

End If

'Following Works for a specific combobox ///////////

'If MyDataGridView.CurrentCellAddress.X = MyDataGridViewComboBox.DisplayIndex Then

' Dim cmb As ComboBox = CType(e.Control, ComboBox)

' If Not cmb Is Nothing Then

' cmb.DropDownStyle = ComboBoxStyle.DropDown

' End If

'End If

End Sub

 

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

'Allow user to enter new values for all DataGridViewComboBox controls in the DataGridView

If (TypeOf CType(sender, DataGridView).EditingControl Is DataGridViewComboBoxEditingControl) Then

Dim cmb As DataGridViewComboBoxEditingControl = CType(CType(sender, DataGridView).EditingControl, DataGridViewComboBoxEditingControl)

If Not cmb Is Nothing Then

Dim grid As DataGridView = cmb.EditingControlDataGridView

Dim value As Object = cmb.Text

'// Add value to list if not there

If cmb.Items.IndexOf(value) = -1 Then

'// Must add to both the current combobox as well as the template, to avoid duplicate entries...

cmb.Items.Add(value)

Dim cmbCol As DataGridViewComboBoxColumn = CType(grid.Columns(grid.CurrentCell.ColumnIndex), DataGridViewComboBoxColumn)

If Not cmbCol Is Nothing Then

cmbCol.Items.Add(value)

End If

End If

grid.CurrentCell.Value = value

End If

End If

 

''Following Works for a specific combobox ///////////

'If e.ColumnIndex = MyDataGridView.Columns("DataGridViewComboBoxColSize").Index Then 'CType(sender, DataGridView).CurrentCell.ColumnIndex

' 'Dim cmb As ComboBox = CType(e.Control, ComboBox)

' Dim cmb As DataGridViewComboBoxEditingControl = CType(CType(sender, DataGridView).EditingControl, DataGridViewComboBoxEditingControl)

' If Not cmb Is Nothing Then

' Dim grid As DataGridView = cmb.EditingControlDataGridView

' Dim value As Object = cmb.Text

' '// Add value to list if not there

' If cmb.Items.IndexOf(value) = -1 Then

' '// Must add to both the current combobox as well as the template, to avoid duplicate entries...

' cmb.Items.Add(value)

' Dim cmbCol As DataGridViewComboBoxColumn = CType(grid.Columns(grid.CurrentCell.ColumnIndex), DataGridViewComboBoxColumn)

' If Not cmbCol Is Nothing Then

' cmbCol.Items.Add(value)

' End If

' grid.CurrentCell.Value = value

' End If

' End If

'End If

''//////////

 

 

End Sub

 

 

Private Sub MyDataGridView_DataError(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewDataErrorEventArgs) Handles MyDataGridView.DataError

'I don't know if this is really necessary.

If e.Exception.Message = "DataGridViewComboBoxCell value is not valid." Then

e.Cancel = True

End If

End Sub

 

 

Hi mcassoc

    The code was very very useful. I have some nitty-gritties

                  1. When I start typing in the combobox the dropdown has to be switched on and autocomplete has to be switched on.

                  2.  And when I press on ENTER that particular data that data has to get selected and move the cursor to the next column not next row 

                  3. Normally I need my cursor to be switched from one column to another when I press ENTER and as well as TAB key

 

Any great Idea are welcome

 Parameswaran.N

 

Answer 26

hey it works..

It saved me a lot of time...

Answer 27

 

the code helped me a lot. Thanks

 

But say I want to validate the data while entering the data inthe combo box...like in general we do it in datagrid_keydown..

 

(Req:I want to validata whether the entered data is number or not..is number only I would like to enter the value in the combo box)

 

But I couldn't get how to assign the validation on the key down on that particular combobox (which I set it as drop down style)

 

plz help me

Answer 28

Please also keep in mind to set the ValueType of your column or you might get DataErrors and in case of use a ComboColumn your selection list may not display correctly.

 

Kind regards

Tom

Answer 29

Thanks for the nice piece of code and advice.

 

I have just a small little problem.. How do I invoke the DataGridView_DataError events handler?

 

My situation is ..

 

I having a combobox and bind it to show data from another table. Basically it's just a list of "item no." field values. Since the user might use the barcode reader. So I have to do some filteration on the code retrieved in from the barcode reader before searching the list in the combo box. If the "item no." value is not there in the list, I want to throw an exception telling the user that the "item no." input is invalid and check on it.

 

 

Thank you in advance for any helps..

 

Regards,

Weoi Li

Answer 30

 

Hi

I have a situation where in I have two combo boxes in a datagridview control. The first combo box items are all static. But the second combo box items need to change based on the first combo box value selected. The problem I am running into is if I bind the datasource to the column the values are all the same all the time and i couldn't see the second combobox values when i select first combobox.

 

Please help me

 

Thanks in Advance,

 

Gangadhar

Answer 31

Hi,

Here is an example using BindingSource Object...

    Private Sub editingComboBox_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs)
        Dim cbo As DataGridViewComboBoxEditingControl = CType(sender, DataGridViewComboBoxEditingControl)
        Dim grid As DataGridView = cbo.EditingControlDataGridView
        Dim value As Object = cbo.Text

        If cbo.Items.IndexOf(value) = -1 Then
            Dim cboCol As DataGridViewComboBoxColumn = CType(grid.Columns(grid.CurrentCell.ColumnIndex), DataGridViewComboBoxColumn)

            ' Create a new row for the DataTable member
            Dim dr As DataRow = Me.m_ds.Tables(0).NewRow()
            dr("ComboboxField") = value

            ' Add row to the datatable
            Me.m_ds.Tables(0).Rows.Add(dr)

            ' Change the current property of the binding source object
            bndComboBox.MoveLast()

            grid.CurrentCell.Value = value
        End If
    End Sub


I'm not completely sure why the bindingsources's current / position property needs to be set.  I thought by setting the grid.CurrentCell.Value that this would be taken care of, but it was not.  Anyone have some insight on this bit of trivia?

Thanks for all everyone's help

Peter

Answer 32

Hy Guys

I also have a problem with a combobox in a datagridview. Here is my code:

 

Dim cmd As OleDbCommand = New OleDbCommand("Select AnneDbut, CycleDbut,AnneFin, CycleFin, Quantit, Dims,Client From TTable", con)

 

Dim cmd2 As OleDbCommand = New OleDbCommand("Select AllDimensions From Dimensions", con)

con.Open()

myDA =

New OleDbDataAdapter(cmd)

myDA2 =

New OleDbDataAdapter(cmd2)

builder =

New OleDbCommandBuilder(myDA)

builder.QuotePrefix =

"["

builder.QuoteSuffix =

"]"

 

myDataSet =

New DataSet()

myDA.Fill(myDataSet,

"MyTable")

DataGridView1.AutoGenerateColumns =

True

myDataSet2 =

New DataSet()

myDA2.Fill(myDataSet2,

"MyDim")

 

Dim comboboxColumn As New DataGridViewComboBoxColumn

comboboxColumn.DataSource = myDataSet2.Tables(

"MyDim").DefaultView  'Here i fill the combobox with the content of the table DIMENSIONS

comboboxColumn.DisplayMember =

"AllDimensions"

comboboxColumn.ValueMember =

"AllDimensions"

comboboxColumn.Name =

"Selected Dimensions"

comboboxColumn.DataPropertyName =

"Dims"

DataGridView1.DataSource = myDataSet.Tables(

"MyTable").DefaultView  'I fill the datagridview with the content of TTable

DataGridView1.Columns.Insert(5, comboboxColumn) 'I insert a column containing the combobox

con.Close()

con =

Nothing

 

Catch ex As Exception

MessageBox.Show(ex.Message)

 

End Try

My goal is  when i start the application, the datagridview will be filled with the content of the table TTable and the combobox should show the value of the column Dims of my TTable and when i click on the combobox column, it would allow me to change the value of the cell. My problem is that I cannot find the way to dispaly the content of the Dims column of my TTable.

Where am I wrong in my code? Could you please help me?

Thanks

Answer 33

Thanks you.... it work for me