membership.html

<script>
function println(msg) {
        document.write( msg+ "<br/>")
    }  

    let member = []
    let key
    let idx 
    let menu 
    let seq
    let id


    seq = 0
    while(1){
        println("1.new member  2.searchID  0 exit")
        menu = Number(prompt("sleect menu :"))
        println("selected menu :" + menu)
        if(menu == 0){
            break
        }
        if(menu == 1){
            id =join()
            if(indexOf_id(id)== -1){
                member[seq] = id
                view_member(member[seq]);
                seq += 1
            }else{
                println("can`t be new member")
            }
        }
        if(menu == 2){
            key = prompt("search id :")
            idx = indexOf_id(key)
            if(idx == -1){
            println("no such id")
    }else{
        println(idx + " : "+ member[idx])
    }
        }
        println("----------------------------")
    }

    function indexOf_id(key) {
        let max = member.length
    for(let i=0;i<max;i++){
        if(key == member[i]){
            return i;
        }
        //println(i+" : "+ member[i])
    }
    return -1
    }

    function view_member(mem){
        println("id :"+ mem)
    }
    function join(){
        let id = prompt("member id :")
        return id

    }
    

   
</script>