一个简单的选课script程序

2023-02-01
<html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
        <title>无标题</title>
        <script type="text/javascript">
        function sum(obj) {
var z = document.getElementById("z");
            var a = document.getElementById("a");
            var b = document.getElementById("b");
            var c = document.getElementById("c");
all.value=parseInt(z.value);
if(a.value!='')
{
y.value=parseInt(a.value);
h.value=parseInt(z.value)-parseInt(a.value);
}
if(a.value!=''&&b.value!='')
{
y.value=parseInt(b.value)+parseInt(a.value);
h.value=parseInt(z.value)-parseInt(a.value)-parseInt(b.value);
}
if(a.value!=''&&b.value!=''&&c.value!='')
{
y.value=parseInt(b.value)+parseInt(a.value)+parseInt(c.value);
h.value=parseInt(z.value)-parseInt(a.value)-parseInt(b.value)-parseInt(c.value);
}
        }
        </script>
    </head>
    <body>
总分：<input type="text" id="z" onkeyup="sum(this);" />
        <input type="text" id="a" onkeyup="sum(this);" />
        <input type="text" id="b" onkeyup="sum(this);" />
        <input type="text" id="c" onkeyup="sum(this);" />
总分：<input type='text' id='all' style="border:0px solid white; width:25px" />
已选：<input type='text' id='y' style="border:0px solid white; width:25px" />
还剩：<input type='text' id='h' style="border:0px solid white; width:25px" />
    </body>
 
</html>