PropertyValueChangedEventArgs.OldValue Property

 

The value of the grid item before it was changed.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public object OldValue { get; }

Property Value

Type: System.Object

A object representing the old value of the property.

This property provides you with the value of the property as it was before the change was applied. You can find the new value by querying the property grid with the specified ChangedItem.

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the PropertyGrid.PropertyValueChanged event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing MessageBox.Show with Console.WriteLine or appending the message to a multiline TextBox.

To run the example code, paste it into a project that contains an instance of type PropertyGrid named PropertyGrid1. Then ensure that the event handler is associated with the PropertyGrid.PropertyValueChanged event.

private void PropertyGrid1_PropertyValueChanged(Object sender, PropertyValueChangedEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "ChangedItem", e.ChangedItem );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "OldValue", e.OldValue );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "PropertyValueChanged Event" );
}

.NET Framework
Available since 1.1
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