javascript动态获取单选按钮信息
我用Foreach动态显示出了单选信息，现在我要在javascript中获取选中的值，怎么做啊？代码如下： 
<c:forEach items="${collList}" var="coll"> 
<input name="collecta" type="radio" value="${coll.id }" 
title="${coll.id }" />${coll.collecttitle } 
<br> 
</c:forEach> 
<input name="Submit" type="button" value="提交"> 
<input name="Submit" type="button" value="查看">

------解决方案--------------------
var all = document.getElementsByTagName( "input" );
for(var i=0;i<all.length;i++)
{
if(all[i].type=='radio'|| all[i].checked==true)
{
alert(document.getElementById('单选框id'));
}
}
------解决方案--------------------

JScript code

    var objArray = document.getElementsByName("collecta");
    for (int i = 0; i < a=objArray.length; i++) {
        if (objArray[i].checked) {
            alert(objArray[i].value);
        }
    }

------解决方案--------------------
JScript code

            var domArray = document.getElementsByName("collecta");
            for (var i = 0; i < domArray.length; i++)
            {
                if (domArray[i].checked)
                {
                    alert(domArray[i].value);
                }
            }