js计算总价

计算总价钱

<script>
 window.onload=function  () {
     var price=document.myform.price;
	 var nums=document.myform.nums;
	 
     var con=document.myform.con;
     nums.onchange=function  () {
	 var aa=nums.selectedIndex+1;
	 
     con.value=aa*parseInt(price.value);
    }
  }
</script>

<form  name="myform" id="form1">
  <input type="text" name="names" value="搜搜" onfocus="if(this.value=='搜搜') this.value=''" onblur="this.value=this.value==''?'搜搜':this.value">
  <input type="button" value="搜索"><br/>
  价钱：<input type="text" value="200" name="price">
  数量:<select name="nums">
          <option>
		     1个
		  </option>
		    <option>
		     2个
		  </option>
		    <option>
		     3个
		  </option>
       </select>
	   
	 总价钱:<input type="text"  name="con">
</form>