winform: binding problem with DropDownList - winforms

I have a table in access database file. I would like to show that table in DataGridView, i have a bindingsource which bind to the table. then DataGridView bind to bindingsource. I also have other controls(textboxs, comboboxs) which are bind to 'dataMember' of table through the same bindingsource. Everything work well. But when i changed 'DropDownStyle' of the combobox from 'DropDown' to 'DropDownList'. The binding is broken. The data in the combobox is not changed when i selected different row in the datagridview. However, when i changed the data in combobox, the data in the cell in DataGridView changed. Anyone has idea? Thank you very much!
The following is my code:
combobox1.Items.AddRange( new Object[]{
"Monday",
"Tuesday",
.....
.....
"Sunday"
});
bindingsource1.DataSource = dt; // dt is a instance of DataTable
combobox1.DataBindings.Add("Text", bindingsource1,"Day");

combobox1.DataBindings.Add("SelectedValue", bindingsource1,"Day");
[EDIT]
Add this:
comboBox1.DisplayMember = "Day";

Related

How to bind a wpf combobox to a DataTable - but do not show duplicate values

Having some trouble figuring this out. So I have a simple combobox, and I bind it to an existing DataTable in the code-behind like so:
roomCombo.ItemsSource = ((IListSource) myDataTable).GetList();
roomCombo.DisplayMemberPath = "Number";
The combobox shows everything i have in the Number column, including duplicates, of course. I'm looking for a way to show only unique values ..
Thanks.
I found a good way to do this:
DataView view = new DataView(myDataTAble);
DataTable distinctValues = view.ToTable(true, columnName);

vb.net - ComboBox with a BindingSource and a different DataSource

In my form I have a DataGridView bound to a BindingSource that has a DataSet as DataSource. I also have some TextFields and ComboBoxes on the form that are bound to different columns in the DataSet through the BindingSource. The idea is that the values in the columns on the selected row in the DataGridView are reflected in the other controls on the form. Maybe I make it sound a bit complicated, but it's fairly easy to connect the TextFields, and also the ComboBoxes bound to tables in the dataset.
My problem is that this time I want to set the items in the ComboBox from an array and not from a table in the DataSet. This is what I've tried:
Me.ComboBox.DataBindings.Add(New System.Windows.Forms.Binding("SelectedValue", Me.TblBindingSource, "ColumnName", True))
Dim ItemArray(2) As String
ItemArray(0) = ""
ItemArray(1) = "Default"
ItemArray(2) = "User-set"
ComboBox.DataSource = ItemArray
Now, this seems to work partially as the ComboBox is populated correctly, and I can select a value, and it appears in the DataGridView. But it doesn't update its selected value as I change rows in the DataGridView. The column ("ColumnName") is a ComboBoxColumn that gets its item list in the way shown above, and it seams to work as expected.
If it wasn't clear; I have several ComboBoxes with similar functionality that works, but they are bound to a column in a DataTable, as follows:
Me.ComboBox1.DataBindings.Add(New System.Windows.Forms.Binding("SelectedValue", Me.Tbl1BindingSource, "WiDMethodX", True))
Me.ComboBox1.DataSource = Me.Tbl2BindingSource
Me.ComboBox1.DisplayMember = "SomeColumn"
Me.ComboBox1.ValueMember = "SomeColumn"
If it matters, the DataSet comes from an Access Database.
SelectedValue is used in conjunction with the ValueMember property, but since your array list doesn't have descriptive fields, that won't work.
Try using SelectedItem for your binding:
Me.ComboBox.DataBindings.Add(New Binding("SelectedItem", _
Me.TblBindingSource, "ColumnName", True))
I realize this questions is old, but I had similar problem I resolved. I bound the text property of the combo box to the binding source member that relates to the value member or display member of my combo box datasource. Make sure that you fill your data tables (for binding source and combo box datasource) AND bind your combo box to its datasource prior to databinding text of combo box.
Dim dtForBindingSource as DataTable
Dim bs as BindingSource
Dim dtForComboBox as DataTable
'Code to fill dtForBindingSource would go here
bs.DataSource = dtForBindingSource
'Code to fill dtForComboBox would go here
ComboBox.DataSource = dtForComboBox
ComboBox.DisplayMember = "ColumnToDisplay"
ComboBox.ValueMember = "ColumnXYZ"
'Now that datasources exist and combo box is set up I do databindings.
ComboBox.DataBindings.Add("Text", bs, "ColumnToDisplay")

Wpf DataGrid with datepicker

How can i access the selected date from datepicker column from the selected row of the wpf datagrid in code behind if i know the datagrid's selected row as
DataRowView drv = datagrid.SelectedItem as DataRowView;
where datagrid is my datagrid's name.
If you bind you datagrid to data, then you can access the selected value on your data object.
If you know the column name then you can get value using
drv["columnName"]

How to bind a DataTable to a WPF DataGrid while filtering the rows and have two-way binding

I have a DataTable that represents a SQL table. The SQL table references itself in a parent/child manner, but only one level (a parent can't have a parent itself)
I want to bind this DataTable to a DataGrid so i can edit the rows on the DataGrid and add new Rows and this should be propagated to the DataTable. So far it's easy.
But now i want to display only the rows that have a parent. From what i understand, if i use a CollectionView to filter the data the changes on the grid won't be propagated to the DataTable. So how can i do that?
what happens if you try to set the defaultview Rowfilter?
var dv = yourDataTableInstance.DefaultView;
dv.RowFilter = "parentcolumn IS NOT NULL";
ItemsSource for the DataGrid is still the datatable but it should be filtered now.

reordering rows in a databound datagridview

I have a DataGridView that is bound to a DataTable, is there a way to reorder the rows in the DataGridView and have the changes reflected in the bound DataTable?
Use a DataView or a BindingSource between the DataTable and the DataGridView, they both have a Sort property :
DataView view = new DataView(table);
view.Sort = "Name ASC, Age Desc";
dataGridView.DataSource = view;
You can also filter the results using the DataView.RowFilter property (or BindingSource.Filter).
The DataGridView will automatically reflect the changes

Resources