足下实训的选择源代码

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>单选</title>
<script type="text/javascript">
   function Check()
   {
       var select_sex = document.getElementsByName("sex");
       if((!document.getElementById("man").checked)&&(!document.getElementById("woman").checked))
       {
           alert("你什么都还没有选呢");
       }
       {
           for(var i = 0;i<select_sex.length;i++)
           {
               if(select_sex[i].checked)
               {
                   alert("选中了"+select_sex[i].value);
                   break;
               }
           }
       }
   }


   function CheckSport()
   {
       var select_sport = document.getElementsByName("sport");
       var arry = new Array();
       var j = -1;
       var f = "";
       for(var i = 0;i<select_sport.length;i++)
       {
           if(select_sport[i].checked)
           {
               j++;
               arry[j] = select_sport[i].value;
           }
       }
       if(arry.length<1)
       {
           alert("你还什么都没有选呢");
       }
       else
       {
           for(var k=0;k<arry.length;k++)
           {
               f+=arry[k];
           }
           alert("我选择了"+f);
       }
   }
</script>
</head>

<body>
   <label><input type="radio" name="sex" id="man" value="男"/>男</label>
    <label><input type="radio" name="sex" id="woman" value="女"/>女</label>
    <label><input type="button" name="check" id="btn_check" value="验证" onclick="Check()"/></label>

    <p></p>
    <label><input type="checkbox" name="sport" id="basketball" value="篮球"/>篮球</label>
    <label><input type="checkbox" name="sport" id="football" value="足球"/>足球</label>
    <label><input type="checkbox" name="sport" id="basketball" value="排球"/>排球</label>
    <label><input type="button" name="check_sport" id="btn_checkSport" value="验证" onclick="CheckSport()"/></label>
</body>
</html>