var xmlhttp;

try
{
	xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
catch (e1)
{
	try
	{
		xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");	
	}
	catch (e2)
	{
		try
		{
			xmlhttp = new XMLHttpRequest();
		}
		catch (e3)
		{
			alert("{# $text.not_ajax #}");
		}
	}
}

var action;
var cityArr = [];
var province;

function setCity(province)
{   
    var url = "ajax.php?a=ajax&game_id=" + province + "&action=getserver";
	xmlhttp.open("GET", url, true);
	//xmlhttp.onreadystatechange=update(province);
	xmlhttp.onreadystatechange = function()
	{
		if (xmlhttp.readyState == 4 && xmlhttp.status == 200) 
    	{
    		var cityArr = [];
			cityArr[province] = xmlhttp.responseText;
		 	arr = eval(cityArr[province]);
			setSelectOption('server_name', arr, '请选择游戏服务器');
		}
	}
	xmlhttp.send(null);
}

function setSelectOption(selectObj, optionList, firstOption, selected)
{
	var temp = document.getElementById(selectObj);
    if (typeof selectObj != 'object')
    {
    	selectObj = temp;
    }
    // alert(selectObj);
    // 清空选项 
    removeOptions(selectObj);
    
    // 选项计数 
    var start = 0;
      
    // 如果需要添加第一个选项 
    if (firstOption)
    {
         selectObj.options[0] = new Option(firstOption, '');
         // 选项计数从 1 开始 
         start++;
    }

    var len = optionList.length;
	//alert(len);
    
    for (var i = 0; i < len; i++)
    {
        // 设置 option 
        selectObj.options[start] = new Option(optionList[i].txt, optionList[i].val);

        // 选中项 
        if (selected == optionList[i].val)
        {
        	selectObj.options[start].selected = true;
        }
        // 计数加 1 
        start++;
    }
}

function removeOptions(selectObj)
{
	if (typeof selectObj != 'object')
    {
    	selectObj = document.getElementById(selectObj);
    }
    
    // 原有选项计数 
    var len = selectObj.options.length;

    for (var i = 0; i < len; i++)
    {
        // 移除当前选项 
        selectObj.options[0] = null;
    }
}