SO - 21658563

by Arun P Johny

HTML

<form id="f">First Name:
    <input type="text" name="input" id="x" size="20" onblur="leave();" />
    <br/>Last Name:
    <input type="text" id="y" size="20" value="enter your name here" />
    <input type="button" value="Check!" onClick="check();" />
</form>

JavaScript

function leave() {
    var x = document.getElementById("x");
    if (x.value == "") {
        alert("please enter your name");
        x.focus();
    }
}

function check() {
    var y = document.getElementById("y");
    if (y.value = "enter your name here") {
        alert("enter your last name");
        y.focus();
        y.select();
    }
}