Javascript-onblur事件在验证中创建无限警报循环

Question

How to make onblur to show 1 alert per validation? It creates infinite loop all the time . I know I can use onchange but I want to do this with onblur event. I heard about something like ( this.id ) method but I don't know how to do it in my code. I heard about flags too, but I don't know what flags do, and again I don't know how to put them in my code.

<form>
        <input type="text" id="liczba1" /><br/>
        <input type="text" id="liczba2" /><br/>
        <input type="text" id="liczba3" />
    </form>
        <input type="submit" id="button" value="Prześlij" onclick="SprawdzWieksze()"/>
    <div id="wynik"></div>
    <script>
    var a = document.getElementById("liczba1");
    var b = document.getElementById("liczba2");
    var c = document.getElementById("liczba3");

        function Waliduja()
        {
            if(isNaN(a.value))
            {
                alert("Nie może być literą!");
                document.getElementById("liczba1").focus();
            }

            else
            {
                return false;
            }
        }

         function Walidujb()
        {
            if(isNaN(b.value))
            {
                alert("Nie może być literą!");
                document.getElementById("liczba2").focus();
            }

            else
            {
                return false;
            }
        }

         function Walidujc()
        {
            if(isNaN(c.value))
            {
                alert("Nie może być literą!");
                document.getElementById("liczba3").focus();
            }

            else
            {
                return false;
            }
        }

        function SprawdzWieksze()
        {
                var a = Number(document.getElementById("liczba1").value);
        var b = Number(document.getElementById("liczba2").value);
        var c = Number(document.getElementById("liczba3").value);

            if(a > b && a > c)
            {
                document.getElementById("wynik").innerHTML = "Największa liczba to: "+a;
            }

            if(b > a && b > c)
            {
                document.getElementById("wynik").innerHTML = "Największa liczba to: "+b;
            }

            if(c > b && c > a)
            {
                document.getElementById("wynik").innerHTML = "Największa liczba to: "+c;
            }
        }

    a.onblur = Waliduja;
    b.onblur = Walidujb;
    c.onblur = Walidujc;

    </script>

Answer 1

But why do you want to do this only on onblur event? The loop occurs because the focus(), like @Viney said.

Using onchange , the application executes without the loop.