Javascriptはselectを作成し、selectの値、テキストを取得する.radio、checkの値を取得します.

//    select  
	                      var s = document.createElement("select") ;
				var d = [{t:'one',v:'1'},{t:'two',v:'2'}] ;
				for(var i in d){					
					 var option = new Option(d[i].t,d[i].v);					
					 s.options.add(option);
				}				
				document.body.appendChild(s);

//       

function show()
{
	var myselect = document.getElementById("select");
	alert(myselect.selectedIndex);
	alert(myselect.options[myselect.selectedIndex].text);
}

function show2(){
	var myselect = document.getElementById("select");
	for(var i=0;i<myselect.length ;i++){
		if(myselect[i].selected == true){
			alert(myselect[i].innerHTML);
		}
	}
}

//  select  
function getSelectedValue(name){
         var obj=document.getElementById(name);
         return obj.value; 
}


//  radio     
function getRadioValue(name){
var radioes = document.getElementsByName(name);
for(var i=0;i<radioes.length;i++)
{
if(radioes[i].checked){
return radioes[i].value;
}
}
return false;
}