F# 将用户名与电子邮件分开

Question

我需要执行将用户名与电子邮件分开的功能。变量名称中有用户名，但我不知道如何 return 它。

let rec email (a:string) =
        let rec loop i (name:string)=
            if a[i] <> '@' then loop (i+1) (name+a[i].ToString())
        loop 0 ""

Answer 1

let rec email (a:string) =
    let rec loop i (name:string)=
        if a[i] <> '@' then loop (i+1) (name+a[i].ToString())
        else name
    loop 0 ""

Answer 2

这里是使用 built-ins

的实现

let email (a: string) = 
    a
    |> Seq.takeWhile (fun c -> c <> '@')
    |> Seq.toArray 
    |> System.String

F# 将用户名与电子邮件分开

F# separating username from email

f#