RadSpinEditor now supports null values. This functionality is relevant for the PropertyGridSpinEditor as well http://docs.telerik.com/devtools/winforms/editors/spineditor/null-value-support
How to use it:
private void RadPropertyGrid1_EditorInitialized(object sender, PropertyGridItemEditorInitializedEventArgs e)
{
PropertyGridSpinEditor editor = e.Editor as PropertyGridSpinEditor;
if (editor!=null)
{
BaseSpinEditorElement el = editor.EditorElement as BaseSpinEditorElement;
el.EnableNullValueInput = true;
}
}
When the editor is activated, pressing Ctrl+Del will clear the value.