指定此升级程序将应用到的最早版本的版本对象或 null （如果未指定.
命名空间： Microsoft.SharePoint.Upgrade
程序集： Microsoft.SharePoint（位于 Microsoft.SharePoint.dll 中）
语法
声明
Public Property BeginVersion As Version
Get
Set
用法
Dim instance As SPUpgradeActionInfo
Dim value As Version
value = instance.BeginVersion
instance.BeginVersion = value
public Version BeginVersion { get; set; }