Ajax相关函数

作者:Fly 日期:2008-08-03

字体大小: 小中大

//@desc    load a page(some html) via xmlhttp,and display on a container
//@param   url          the url of the page will load,such as "index.php"
//@param   request      request string to be sent,such as "action=1&name=surfchen"
//@param   method       POST or GET
//@param   container          the container object,the loaded page will display in container.innerHTML
//@usage
//         ajaxLoadPage('index.php','action=1&name=surfchen','POST',document.getElementById('my_home'))
//         suppose there is a html element of "my_home" id,such as "<span id='my_home'></span>"
//@author  SurfChen <surfchen@gmail.com>
//@url     http://www.surfchen.org/
//@license http://www.gnu.org/licenses/gpl.html GPL
function ajaxLoadPage(url,request,method,container)
{
    method=method.toUpperCase();
    var loading_msg='Loading...';//the text shows on the container on loading.
    var loader=new XMLHttpRequest;//require Cross-Browser XMLHttpRequest
    if (method=='GET')
    {
        urls=url.split("?");
        if (urls[1]=='' || typeof urls[1]=='undefined')
        {
            url=urls[0]+"?"+request;
        }
        else
        {
            url=urls[0]+"?"+urls[1]+"&"+request;
        }

        request=null;//for GET method,loader should send NULL
    }
    loader.open(method,url,true);
    if (method=="POST")
    {
        loader.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
    }
    loader.onreadystatechange=function(){
        if (loader.readyState==1)
        {
            container.innerHTML=loading_msg;

        }
        if (loader.readyState==4)
        {
            container.innerHTML=loader.responseText;
        }
    }
    loader.send(request);
}
//@desc    transform the elements of a form object and their values into request string( such as "action=1&name=surfchen")
//@param   form_obj          the form object
//@usage   formToRequestString(document.form1)
//@notice  this function can not be used to upload a file.if there is a file input element,the func will take it as a text input.
//         as I know,because of the security,in most of the browsers,we can not upload a file via xmlhttp.
//         a solution is iframe.
//@author  SurfChen <surfchen@gmail.com>
//@url     http://www.surfchen.org/
//@license http://www.gnu.org/licenses/gpl.html GPL
function formToRequestString(form_obj)
{
    var query_string='';
    var and='';
    //alert(form_obj.length);
    for (i=0;i<form_obj.length ;i++ )
    {
        e=form_obj[i];
        if (e.name!='')
        {
            if (e.type=='select-one')
            {
                element_value=e.options[e.selectedIndex].value;
            }
            else if (e.type=='checkbox' || e.type=='radio')
            {
                if (e.checked==false)
                {
                    break;
                }
                element_value=e.value;
            }
            else
            {
                element_value=e.value;
            }
            query_string+=and+e.name+'='+element_value.replace(/\&/g,"%26");
            and="&"
        }

    }
    return query_string;
}
//@desc    no refresh submit(ajax) by using ajaxLoadPage and formToRequestString
//@param   form_obj          the form object
//@param   container          the container object,the loaded page will display in container.innerHTML
//@usage   ajaxFormSubmit(document.form1,document.getElementById('my_home'))
//@author  SurfChen <surfchen@gmail.com>
//@url     http://www.surfchen.org/
//@license http://www.gnu.org/licenses/gpl.html GPL
function ajaxFormSubmit(form_obj,container)
{
    ajaxLoadPage(form_obj.getAttributeNode("action").value,formToRequestString(form_obj),form_obj.method,container)
}