JS实现简单的判断文本框长度

有点点JS基础的人都可以看得明白，那么就不多说，直接上代码

JS代码如下

function chargeid() {
    var x, text;
    x=document.login.name.value;
    // 如果输入的值 x 不是数字或者小于 1 或者大于 10，则提示错误 Not a Number or less than one or greater than 10
    if (x.length<4||x.length>9) {
        text = "用户名长度应该为5-9之间"
        document.getElementById("charge1").innerHTML = text;
        return false;//阻止表单提交
    } else {
        text = "输入正确";
        document.getElementById("charge1").innerHTML = text;
        return true;
    }
}

HTML代码（自动忽略属性）

<div class="logo"></div>
<form name = "login" method="post" onSubmit= "return chargeid();">

    <div class="form-item">
        <input id="username" type="text" autocomplete="off" placeholder="用户名" name = "name" required="required">
        <p class="tip" id="charge1"></p>
    </div>
    <div class="form-item">
        <input id="password" type="password" autocomplete="off" placeholder="登录密码" name = "password" required="required">
        <p class="tip">密码不正确</p>
    </div>

    <div class="form-item">
        <button type="submit" class="button1">登 录</button>
    </div>
</form>