How to use FlagTypeSingle/FlagTypeNeedVar/FlagTypeNeedSet/FlagTypeSkipUnknown for design a UEFI Shell program?

SHELL_VAR_CHECK_ITEM TestCheckList[] = {
  {
    L"+a",
    0x01,
    0x02,
    FlagTypeSingle /*example: +a(nothing is behind this parameter.)*/
  },
  {
    L"-a",
    0x02,
    0x01,
    FlagTypeSingle /*example: -a(nothing is behind this parameter.)*/
  },
  {
    L"-b",
    0x03,
    0,
    FlagTypeNeedVar /*example: -b 20(that has space between the two parameters.)*/
  },
  {
    L"-c",
    0x04,
    0,
    FlagTypeNeedSet /*example: -c20(that doesn't has any space between the two parameters.)*/
  },
  {
    L"-z",
    0x05,
    0,
    FlagTypeSkipUnknown /*This flag would cause system hang currently. -z */
  },
  {
    L"-?",
    0x02,
    0,
    FlagTypeSingle
  },
  {
    NULL,
    0,
    0,
    0 /*List End*/
  }
};