js checkbox(复选框) 使用集锦

function selectAll() //全选
{
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() //反选
{
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() //得到批量处理的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() //得到批量处理的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()　　//把选择到的值写到文本框
{
　var userIds = new Array();
userIds = idArray();
　　var userIdString = userIds.join(","); 　//数组字符串化
　　 document.getElementById('member').value=userIdString;
}