<script type="text/javascript">
    alert("你好，"+‘\n‘+"这是第二行内容");
</script>

<script type="text/javascript">
    function disp_prompt(){
            var name=  prompt("Please enter you name","Aqua");
            
            if(name!=null && name!=""){
                    document.write("Hello "+name+" !How are you today?");
                }
        }

</script>

<input type="button"  onclick="disp_prompt()" value="单击来看看有什么"  />

<script type= "text/javascript">
    function disp_confirm(){
            var r = confirm("Press a Button");
            if(r == true){
                        document.write("You Processed OK");
                    }else{
                            document.write("You Process Cancel");
                        }
        }
</script>
<input type="button" onclick="disp_confirm()" value ="显示窗口来看看" />