語法

在F＃編程語言中if / then / elif / else語句的語法是 

if expr then
   expr
elif expr then
   expr
elif expr then
   expr
...
else
   expr

實(shí)例

let a : int32 = 100

(* check the boolean condition using if statement *)

if (a = 10) then
   printfn "Value of a is 10\n"
elif (a = 20) then
   printfn " Value of a is 20\n"
elif (a = 30) then
   printfn " Value of a is 30\n"
else
   printfn " None of the values are matching\n"
   printfn "Value of a is: %d" a

當(dāng)編譯和執(zhí)行程序時，它會產(chǎn)生以下輸出 

None of the values are matching

Value of a is: 100