DBrowse class structure:
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create class DBrowse from Browse
  export:
    var Alias      //""
    var RecNo      //0
    var IndexNo    //0
    var FilterNo   //0
    var FilterExp  //""
    var FilterBExp //{||false}
    var FilterMark //false
    var OneDbf     //(object of OneDbf)
    method New=DBrowseNew                 //o:New() --> self
    method DoGet=DBrowseDoGet             //o:DoGet() --> true/false
    method PostInit=DBrowsePostInit       //o:PostInit() --> true
    method SwapForm=DBrowseSwapForm       //o:SwapForm() --> true
    method UpDatabase=DBrowseUpDatabase   //o:UpDatabase() --> true
    method UpFilter=DBrowseUpFilter       //o:UpFilter() --> true
    method VPaint=DBrowseVPaint           //o:VPaint() --> true
    method VProcess=DBrowseVProcess       //o:VProcess() --> true
    endclass