BindingsCollection Class
Assembly: System.Windows.Forms (in system.windows.forms.dll)
Simple data binding is accomplished by adding Binding objects to a BindingsCollection. Any object that inherits from the Control class can access the BindingsCollection through the DataBindings property. For a list of Windows controls that support data binding, see the Binding class.
The following example binds the Text property of a TextBox control to a field in a database.
Private Sub BindTextBoxControl() Dim myDataSet As New DataSet() ' Insert code to populate the DataSet with tables, columns, and data. ' Creates a new Binding object. Dim myBinding As New Binding("Text", myDataSet, _ "customers.custToOrders.OrderAmount") ' Adds event delegates for the Parse and Format events. AddHandler myBinding.Parse, AddressOf CurrencyToDecimal AddHandler myBinding.Format, AddressOf DecimalToCurrency ' Adds the new Binding to the BindingsCollection. text1.DataBindings.Add(myBinding) End Sub Private Sub DecimalToCurrency(sender As Object, _ cevent As ConvertEventArgs) ' This method is the Format event handler. Whenever the ' control displays a new value, the value is converted from ' its native Decimal type to a string. The ToString method ' then formats the value as a Currency, by using the ' formatting character "c". cevent.Value = CDec(cevent.Value).ToString("c") End Sub Private Sub CurrencyToDecimal(sender As Object, _ cevent As ConvertEventArgs) ' This method is the Parse event handler. The Parse event ' occurs whenever the displayed value changes. The static ' Parse method of the Decimal structure converts the ' string back to its native Decimal type. cevent.Value = Decimal.Parse(cevent.Value.ToString(), _ NumberStyles.Currency, nothing) End Sub
private void BindTextBoxControl()
{
DataSet myDataSet = new DataSet();
/* Insert code to populate the DataSet with tables,
columns, and data.
*/
// Creates a new Binding object.
Binding myBinding = new Binding("Text", myDataSet,
"customers.custToOrders.OrderAmount");
// Adds event delegates for the Parse and Format events.
myBinding.add_Parse(new ConvertEventHandler(CurrencyToDecimal));
myBinding.add_Format(new ConvertEventHandler(DecimalToCurrency));
// Adds the new Binding to the BindingsCollection.
text1.get_DataBindings().Add(myBinding);
} //BindTextBoxControl
private void DecimalToCurrency(Object sender, ConvertEventArgs cevent)
{
/* This method is the Format event handler. Whenever the
control displays a new value, the value is converted from
its native Decimal type to a string. The ToString method
then formats the value as a Currency, by using the
formatting character "c".
*/
cevent.set_Value(((System.Decimal)(cevent.get_Value())).ToString("c"));
} //DecimalToCurrency
private void CurrencyToDecimal(Object sender, ConvertEventArgs cevent)
{
/* This method is the Parse event handler. The Parse event
occurs whenever the displayed value changes. The static
Parse method of the Decimal structure converts the
string back to its native Decimal type.
*/
cevent.set_Value(Decimal.Parse(cevent.get_Value().ToString(),
NumberStyles.Currency, null));
} //CurrencyToDecimal
System.MarshalByRefObject
System.Windows.Forms.BaseCollection
System.Windows.Forms.BindingsCollection
System.Windows.Forms.ControlBindingsCollection
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.