js checkbox(複選框) 使用集錦

function selectAll() //全選
{
var objs = document.getElementsByName('twId');
var i;
for(i = 0; i < objs.length; i++)
{
if(objs[i].type == "checkbox")
{
objs[i].checked = true;
}
}
}
function unselect() //反選
{
var objs = document.getElementsByName('twId');
var i;
for(i=0;i<objs.length;i++)
{
if(objs[i].type=='checkbox')
{
if(objs[i].checked == true)
{
objs[i].checked =false;
}
else
{
objs[i].checked =true;
}
}
}
}
function idArray() //得到批量處理的twId
{
var objs = window.document.getElementsByName('twId');
var i;
var idArray = new Array();
var j = 0;
for(i=0;i<objs.length;i++)
{
if(objs[i].type=='checkbox')
{
if(objs[i].checked == true)
{
idArray[j] = objs[i].value;
j = j + 1;
}
}
}
return idArray;
}
function evArray() //得到批量處理的city
{
var objs = window.document.getElementsByName('twId');
var evObj = window.document.getElementsByName('cityStr');
var i;
var evArray = new Array();
var j = 0;
for(i=0;i<objs.length;i++)
{
if(objs[i].type=='checkbox')
{
if(objs[i].checked == true)
{
evArray[j] = evObj[i].value;
j = j + 1;
}
}
}
return evArray;
}
function selectUser()　　//把選擇到的值寫到文字框
{
　var userIds = new Array();
userIds = idArray();
　　var userIdString = userIds.join(","); 　//數組字串化
　　 document.getElementById('member').value=userIdString;
}