对checkbox的全部选中和提取选中项的操作

 

代码：

<form>
<input name='chkAll' type='checkbox' id='chkAll' onclick='CheckAll(this.form)' value='checkbox'>全部选中<br/>
<input name='pid' type='checkbox' id='checkbox1' value=''><br/>
<input name='pid' type='checkbox' id='checkbox2' value=''><br/>
<input name='pid' type='checkbox' id='checkbox3' value=''><br/>
<input name='pid' type='checkbox' id='checkbox4' value=''><br/>
<input name='pid' type='checkbox' id='checkbox5' value=''><br/>
<input name='pid' type='checkbox' id='checkbox6' value=''><br/>


<input id="Button1" type="button" value="选择了哪些？" onclick="deletes(this.form)" />
</form>
<script type="text/javascript">
function deletes(form)//删除
{
    var selects="";
    for (var i=0;i<form.elements.length;i++)
    {
        var e = form.elements[i];
        if(e.name=="pid")
        {
            if(e.checked==true)
            {
                selects+=e.id+",";
            }
        }
    }
    if(selects=="")
    {
    alert("请先选择选项！");
    return;
    }
 alert(selects);
}


function CheckAll(form)//全部选中
  {
  for (var i=0;i<form.elements.length;i++)
    {
    var e = form.elements[i];
    if (e.Name != "chkAll"&&e.disabled==false)
       e.checked = form.chkAll.checked;
    }
  }
</script>