Xceed DataGrid for WPF v7.2 Documentation
PreemptivePageQueryRatio Property (DataGridVirtualizingCollectionViewSourceBase)


Xceed.Wpf.DataGrid Assembly > Xceed.Wpf.DataGrid Namespace > DataGridVirtualizingCollectionViewSourceBase Class : PreemptivePageQueryRatio Property
Gets or sets a value representing the percentage from the start or the end of a page that, when accessed, will cause the previous or next page to be queried and the items loaded in memory.
Syntax
'Declaration
 
Public Property PreemptivePageQueryRatio As Double
'Usage
 
Dim instance As DataGridVirtualizingCollectionViewSourceBase
Dim value As Double
 
instance.PreemptivePageQueryRatio = value
 
value = instance.PreemptivePageQueryRatio
public double PreemptivePageQueryRatio {get; set;}

Property Value

A value between 0.0 and 0.5 that represents the percentage from the start or the end of a page that, when accessed, will cause the previous or next page to be queried and the items loaded in memory. By default, 0.25 meaning that when an item is accessed and is part of the first 25 If the item is located in the last 25 of a page, a QueryItems event will be raised to request the data for the next page.
Remarks
If the PreemptivePageQueryRatio property is set to 0.5, the previous and next pages will always be fetched. If set to 0.0, this feature will be disabled and the QueryItems event will only be raised when the requested item is not part of the in-memory page.
Requirements

Target Platforms: Windows 11, Windows, 10, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also

Reference

DataGridVirtualizingCollectionViewSourceBase Class
DataGridVirtualizingCollectionViewSourceBase Members