Javascript：显示带有复选框值的图像

我目前正在使用单选按钮和复选框来在 javascript 的帮助下显示图像。具体来说：我在处理复选框和显示图像时遇到问题。使用单选按钮时，只会显示该类别的一张图像。但对于复选框，需要显示多个图像。例如，用户可以检查夹克和手套的字段，并且将显示两张图片。

如何格式化函数以在单击复选框时显示多张图片？EXAMPLE http://webprolearner2346.zxq.net/bike_calculator/

JS

<script language="JavaScript" type="text/javascript">

function check_value(val, id, type) {     
    var el = document.getElementById("imgBox" + id);
    if (val>0 && val<4) { //will trigger when [1,2,3]
       el.src = "images/"+ type + val + ".jpg";
       el.style.display = "";
  }    
  }      

</script>

HTML

<h2>Choose a bike</h2>
<form name="builder">
    <input type="radio" name="field" value="1" onclick='check_value(1, 1, "bike")'/> KAWASAKI KX 450F<br />
    <input type="radio" name="field" value="2" onclick='check_value(2, 1, "bike")'/> 2010 Yamaha Road Star S<br />
    <input type="radio" name="field" value="3" onclick='check_value(3, 1, "bike")'/> Aprilia RSV4<br />
</form>

<img id="imgBox1" src="#" style="display:none"> 

<h2>Choose a tire</h2>  
<form name="tire">
    <input type="radio" name="field" value="1" onclick='check_value(1, 2, "tire")'/> Michelin Pilot Road 3 Tires<br />
    <input type="radio" name="field" value="2" onclick='check_value(2, 2, "tire")'/> Dunlop Roadsmart Sport-Touring Tires<br />
    <input type="radio" name="field" value="3" onclick='check_value(3, 2, "tire")'/> Pirelli Scorpion Trail Tires<br />
</form>

<img id="imgBox2" src="#" style="display:none">

<h2>Choose Accesories</h2>
<form name="tire">
    <input type="checkbox" name="field" value="1" onclick='check_value(1, 3, "accesories")'/> Chrome Front Plate<br />
    <input type="checkbox" name="field" value="2" onclick='check_value(2, 3, "accesories")'/> Jacket<br />
    <input type="checkbox" name="field" value="3" onclick='check_value(3, 3, "accesories")'/> Gloves            
</form>

<img id="imgBox3" src="#" style="display:none">

<form name="tire">
    <input type="checkbox" name="field" value="1" onclick='check_value(1, 3, "accesories")'/> Chrome Front Plate<br />
    <input type="checkbox" name="field" value="2" onclick='check_value(2, 3, "accesories")'/> Jacket<br />
    <input type="checkbox" name="field" value="3" onclick='check_value(3, 3, "accesories")'/> Gloves            
</form>
<div id='access'></div>    

function check_value(val, id, type) {     
        var img = document.createElement("img");
    img.src = "http://webprolearner2346.zxq.net/bike_calculator/images/"+type+val+".jpg";
    alert(img.src)
    var src = document.getElementById("access");
    src.appendChild(img);
      }   

检查这个演示fiddle http://jsfiddle.net/u37tN/2/