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CacheVirtualItemsEventArgs.StartIndex Property

Definition

Gets the starting index for a range of values needed by a ListView control in virtual mode.

public:
 property int StartIndex { int get(); };
public int StartIndex { get; }
member this.StartIndex : int
Public ReadOnly Property StartIndex As Integer

Property Value

The index at the start of the range of values needed by the ListView control.

Examples

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the ListView.CacheVirtualItems 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 ListView named ListView1. Then ensure that the event handler is associated with the ListView.CacheVirtualItems event.

private void ListView1_CacheVirtualItems(Object sender, CacheVirtualItemsEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "StartIndex", e.StartIndex );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "EndIndex", e.EndIndex );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "CacheVirtualItems Event" );
}
Private Sub ListView1_CacheVirtualItems(sender as Object, e as CacheVirtualItemsEventArgs) _ 
     Handles ListView1.CacheVirtualItems

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "StartIndex", e.StartIndex)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "EndIndex", e.EndIndex)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"CacheVirtualItems Event")

End Sub

Remarks

The range of values specified by the StartIndex and EndIndex properties represents the range of values most likely needed by a virtual ListView control for the next occurrence of a RetrieveVirtualItem event.

Applies to