/// <summary>
/// Execute tie script statements with Host instance synchronized,and CodeBlock is resident
/// keyword this in the script pointer to host instance
/// </summary>
/// <param name="src">source code</param>
/// <param name="instance">Host instance</param>
public void Execute(string src, object instance)
{
//支持this操作符,但是this.xxx只能是public成员
this.scope = "THIS";
DS.AddObject(this.scope, instance);
SyncInstance(instance, false);
Execute(src, CodeType.statements, CodeMode.Append); //缺省: 保留statements的代码在module上面
SyncInstance(instance, true);
}