<Page
…
xmlns:ig="http://schemas.infragistics.com/xaml"
xmlns:igPrim="http://schemas.infragistics.com/xaml/primitives"
…>
<Button Content="Zoom to 100%"
ig:Commanding.CommandTarget="{Binding ElementName=xamSpreadsheet1}">
<ig:Commanding.Command>
<igPrim:SpreadsheetCommandSource
EventName="Click"
CommandType="ZoomTo100" />
</ig:Commanding.Command>
</Button>