JavaScript 学习（二）-优快云博客

本文链接：https://blog.youkuaiyun.com/princegang/article/details/83289942

JavaScript中类的学习，从基本类继承过来方法
也可以这样实现：


   function newClass(){
        this.firstName="frank";
        this.toUc=String.toUpperCase;
        this.toString=function(){
           return this.toUc(this.firstName);
        }
    }
    var nc=new newClass();
    alert(nc);//在IE中没反应。。

一个简单的客户端验证


<html>
<head>
  <title>javascript</title>
    <script type="text/javascript">
        function doSubmit(inForm){
            if(inForm.firstName.value==""){
                alert("firstName is null");
                return false;
            }
            if(inForm.lastName.value ==""){
                alert("lastName is null");
            }
            inForm.submit();
            return true;
        }
    </script>
</head>
<body>
<form action="#" name="test" method="post">
    First name: <input type="text" name="firstName">
    <br>
    Last name:<input type="text" name="lastName">
    <br>
    <input type="button" value="submit" onclick="doSubmit(this.form);">
</form>
</body>
</html>
</form>

一般这样写


<form action="#" name="test" method="post" onSubmit="return doSubmit(this);">
    First name: <input type="text" name="firstName">
    <br>
    Last name:<input type="text" name="lastName">
    <br>
    <input type="button" value="submit" >