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Add dropdown list to DataGrid columns and populate rows at runtime C#

My end goal is to populate a DataGrid with data retrieved from a database at runtime. My methodology is to pull all the columns from that database first and then pull the corresponding data for each column for each row as below:
ReadOnlyCollection<Field> tablefields = {//has the fields populated from the database};
//adding all the columns to the data table
var datatable = new DataTable("mytable");
foreach (var field in tablefields)
{ datatable.Columns.Add(field.Name, wFieldType); }
//Then add the rows
while (cursor.MoveNext())
{
var tableRow = datatable.NewRow();
var row = cursor.Current;
for(var i = 0; i < tablefields.Count; i++)//add the values for each field to the data table.
{
tableRow[i] = row[i] ?? DBNull.Value;
}
datatable.Rows.Add(tableRow);
}
My problem however is that some of the columns that I am pulling have to be in the form of a DataGridComboBoxColumn since they have preset values in a dropdown list in the database. The best case scenario would have been that as I pull the columns into my dataTable one by one, I would detect the ones that have preset values and make those oftype DataGridComboBoxColumn before adding them to the dataTable. I obviously can't do that because you cannot have a combobox on a dataTable. My next option is to use the dataGrid to load the columns and the data from the database at runtime.
I am able to add the columns with a combobox as shown in the code below but I cannot figure out how to get my data from the database into the dataGrid containing the pre-loaded columns.
DataGridComboBoxColumn cb = new DataGridComboBoxColumn();
cb.ItemsSource = new List(){to be populated later}
cb.Header = field.Name;
MyDataGrid.Columns.Add(cb);
The code above was used as a sample to test the DataGridComboBoxColumn and sure enough I was able to see the datagrid with the comboboxes. I just can't figure out how to get my database data into the table. I would appreciate any ideas.
PS: I cannot use datagridview because of the api that I am working with so I am limited to datagrid.

You should set the SelectedItemBinding to a binding to a column in your DataTable that contains the value in the ItemsSource to be selected:
cb.SelectedItemBinding = new Binding("AColumnInYourDataTable");
If you set the ItemsSource to a List<T> where T is a complex type, you should instead set the SelectedValueBinding and SelectedValuePath and DisplayMemberPath properties:
cb.SelectedValueBinding = new Binding("AColumnInYourDataTable");
cb.SelectedValuePath = "NameOfThePropertyOfTThatHoldsTheValue";
cb.DisplayMemberPath = "NameOfAPropertyOfTThatHoldsTheDisplayName";

Using a list retrieved from a SQLite query in a 'foreach' statement

I'm currently converting some code that stores data in an XML file to storing it in a SQLite database instead. The database has a single table with 4 columns:
thumbnail | title | threadid | url
All of the entries in the database are strings. With my old code, I extract all the data from an XML file and populate a datagrid with the values. My aim is to do just that but using data pulled from the SQLite database. I can successfully extract all the data from the database table like so:
public List<Database> getFromTable()
{
List<Database> items = new List<Database>();
string sql = "SELECT * FROM blacklist";
SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
using (SQLiteDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
var item = new Database();
item.imgstring = (string)reader["thumbnail"];
item.titlestring = (string)reader["title"];
item.threadidstring = (string)reader["threadid"];
item.urlstring = (string)reader["url"];
items.Add(item);
}
}
return items;
}
The part I'm now stuck on is how to use the results returned in the list. Currently I'm calling the method like so:
var items = database.getFromTable();
However after failing to find some examples, I can't work out how to put the foreach line together use the items in the returned list. Eg;
foreach (??? in items)
{
// Populate line in datagrid with thumbnail, title, threadid, url
}
I can get the datagrid populated, it's just understanding how to breakdown my 'items' into a usable form. Any pointers appreciated.
Edit I will be adding this information into a data-grid so each cell value from the SQLite table will be added into a matching cell on the data-grid.
Edit 2 It's worth mentioning that while thumbnail from my SQLite database is a string value, it's actually an image that's been converted to a Base64ImageRepresentation so I can store it as a string value. Part of getting each value from the SQLite database is so I can convert this string back to an image before adding in into my DataGridView.

It would be easier to forego the custom objects, and instead just read a DataTable and use it as the source of the DataGridView directly.
If you must use the custom objects, then you will have to loop over them, create rows from the grid's data source, and populate the rows one by one, adding them back once populated.
Something like this:
foreach (var item in getFromTable())
{
var index = grid.Rows.Add();
var row = grid.Rows[index];
row.SetValues(item.imgstring, item.titlestring, item.threadidstring, item.urlstring); //order of the items must match field order in grid
}
Still, I would opt for the option of binding to a solid data source. But this should give you the general idea.

C# - How to check if the user's input is present in the ComboBox (used Data Bound Items)

I used the Winform's Data Bound Items in my ComboBox to connect it to one of my tables in my MS Access Database.
How can I check if the user's input is existing in the Data Source bounded to my ComboBox?

I assume that you set combobox datasource like this
DataTable dt = getData();
cmbbox1.DataSource = dt;
//define DisplayMember and ValueMember
and then you can check like this
var somedata = dt.AsEnumerable().Where(p=>p["DisplayMemberFieldName"] = UserInput).FirstOrDefault();

how to remove (not hiding) columns from a DevExpress gridView?

I load my data into a GridView using DataSet. At first databinding, it works well. But when I run query that return different columns, the GridView show the new column plus the old one. I've tried the gridView1.Columns.Clear() method, but it doesn't solve the problem.
Here are some of the code:
// loading data into dataset
dataSet dsGrid = new dataSet();
string dtMember = "kpi";
// note: "thequery" is query generated based on user's selection
using (MySqlDataAdapter da = new MySqlDataAdapter(thequery, myCn))
{
da.Fill(dsGrid, dtMember);
}
// set the gridControl's datasource
gc_report.DataSource = null;
// clear the columns
gridView1.Columns.Clear();
// bind the data
gc_report.DataSource = dsGrid;
gc_report.DataMember = dtMember;
When I run my application, it runs well, but if the query return different column, the old column still appear although I've put the Clear() method of the gridView1.Columns collection.
How to set the gridView1 , so the grid always shows the current query?

how to update dataGrid in database

In my C# project, i populated the values in DataGrid from DataTable. Now if i make changes in the values in the DataGrid i need to update them in the DataBase. I'm using MS access.
Here is the code snippet of how i populate values in the DataGrid.
while (myReader.Read())
{
frmBind.dr = frmBind.dtResults.NewRow();
frmBind.dr["ClassName"] = myReader.GetString(0);
frmBind.dr["MethodSignature"] = myReader.GetString(1);
frmBind.dr["ParameterValues"] = myReader.GetString(2);
frmBind.dr["ExpectedResults"] = myReader.GetString(3);
frmBind.dtResults.Rows.Add(frmBind.dr);
}
frmBind.dataGrid2.DataSource = frmBind.dtResults;
where,
dtResults is DataTable,
frmBind is a Class Object,
dataGrid2 is the DataGrid,
myReader.Read() is used to get the values from the DataBase.

I suggest you drop the datareader.
Drag an SQLDataSource onto the page and configure it with your query. It will give you reading/updating without writing any code at all.