The below mentioned codes explains the methods of customizing the ribbon in SharePoint, programmatically.
Hide a Ribbon
  1. public void HideRibbon()
  2. {
  3. SPRibbon spRibbon = SPRibbon.GetCurrent(this.Page);
  4. if (SPRibbon != null && !this.Page.Request.IsAuthenticated)
  5. {
  6. SPRibbon.CommandUIVisible = false;
  7. }
  8. }
Hide a Ribbon Group
  1. SPRibbon spRibbon = SPRibbon.GetCurrent(this.Page);
  2. if (spRibbon != null)
  3. {
  4. spRibbon.TrimById(“RibbonGroupId”);
  5. }
Hide a single ribbon button
  1. public void HideRibbonItem()
  2. {
  4. SPRibbon spRibbon = SPRibbon.GetCurrent(this);
  5. spRibbon.TrimById("Ribbon.ListItem.New.NewFolder");
  6. }