You can bind a combo box to a DataReader. A DataReader lets you access data in a read-only, forward-only way from a data source. Using a DataReader is often a quick way of returning results as this example shows for populating results in a combo box.
Example
| C# |
 Copy Code |
/// Set up a connection to the database.
string dbpath = "c:\\reader.mdb";
System.Data.OleDb.OleDbConnection dbConn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;DATA SOURCE=" + dbpath);
/// Open a connection and a SELECT command.
dbConn.Open();
System.Data.OleDb.OleDbCommand dbCommand = new System.Data.OleDb.OleDbCommand("SELECT * FROM Table1", dbConn);
/// Open a DataReader on that connection and command.
System.Data.OleDb.OleDbDataReader dr = dbCommand.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
/// Loop through the rows returned by the reader.
ArrayList al = new ArrayList();
while (dr.Read()) {
al.Add(dr("Data"));
}
/// Populate combo box with data converted to strings.
string[] s;
s = al.ToArray(typeof(string));
FarPoint.Win.Spread.ComboBoxCellType cb = new FarPoint.Win.Spread.ComboBoxCellType();
cb.Items = s;
FpSpread1.ActiveSheetView.Cells(0, 0).CellType = cb;
/// Dispose connection.
dbConn.Dispose();
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| VB |
Copy Code |
' Set up a connection to the database.
Dim dbpath As String = "c:\reader.mdb"
Dim dbConn As New System.Data.OleDb.OleDbConnection( _
"Provider=Microsoft.Jet.OLEDB.4.0;DATA SOURCE=" & dbpath)
' Open a connection and a SELECT command.
dbConn.Open()
Dim dbCommand As New System.Data.OleDb.OleDbCommand( _
"SELECT * FROM Table1", dbConn)
' Open a DataReader on that connection and command.
Dim dr As System.Data.OleDb.OleDbDataReader = dbCommand.ExecuteReader(System.Data.CommandBehavior.CloseConnection)
' Loop through the rows returned by the reader.
Dim al As New ArrayList()
While dr.Read()
al.Add(dr("Data"))
End While
' Populate combo box with data converted to strings.
Dim s As String()
s = al.ToArray(GetType(String))
Dim cb As New FarPoint.Win.Spread.ComboBoxCellType
cb.Items = s
FpSpread1.ActiveSheetView.Cells(0, 0).CellType = cb
' Dispose connection.
dbConn.Dispose()
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