字符日期 改正式日期 (14482)

C2=TEXT(SUM(MID(SUBSTITUTE(B2,"/",REPT(" ",99)),{3,2,1}*99-98,99)*10^{4,2,0}),"0!/00!/00")

另解=TEXT(SUM(TEXT({0,-1,1}%,SUBSTITUTE(B2,"/",";"))*10^{4,2,0}),"0!/00!/00")