JavaScript实时验证表单没反应

[ft859715]

想判断表单是否为空，如果失去焦点后表单为空的话，后面的label显示“账号不能为空”，但是么反应，下面是代码，大家帮我看看吧

<script type="text/javascript">
        function chkAccount(){
		var val=document.getElementsByName("account").value;
		if(val=""){
			document.getElementById("alert_account").innerHTML="账号不能为空";
			form.account.focus();
			return false;
			}
		}
</script>

<form action="register_check.php" method="post" name="form">
            <div class="attribute account">
              <label for="person_account">账号</label><br />
              <input id="person_account" name="account" size="30" type="text" onblur="return chkAccount()"/>
              <label id="alert_account"></label>
            </div>
            
</form>

[sohighthesky]

var val=document.getElementsByName("account")[0].value;

or

var val=document.getElementById("person_account").value;

[sohighthesky]

The method document.getElementsByName returns a nodelist

[ft859715]

还是没用啊