//检查输入是否是数字
        function checkNaN()
        {
            var result=false;
            var keyCodes=new Array(8,37,38,39,40,46,48,49,50,51,52,53,54,55,56,57,96,97,98,99,100,101,102,103,104,105,190,110);
            for(var i=0;i<keyCodes.length;i++)
            {
                if(Number(keyCodes[i])==Number(event.keyCode))
                {
                    result=true;
                    break;
                }
            }
            return result;
        }
        
        //检查输入是否是正整数
        function checkNaN2()
        {
            var result=false;
            var keyCodes=new Array(8,48,49,50,51,52,53,54,55,56,57,96,97,98,99,100,101,102,103,104,105,190);
            for(var i=0;i<keyCodes.length;i++)
            {
                if(Number(keyCodes[i])==Number(event.keyCode))
                {
                    result=true;
                    break;
                }
            }
            return result;
        }
        
        
    function createXMlHttpRequest()
    {        
		var httpOb;
		try
		{
		    httpOb = new XMLHttpRequest();
		}
		catch(e)
		{
		    try
		    {
		        httpOb = new ActiveXObject("Msxml2.XMLHTTP");
		    }
		    catch(e)
		    {
		        httpOb = new ActiveXObject("Microsoft.XMLHTTP");
		    }
		}
		return httpOb;
    }
    function createXMlDoc()
    {        
		var xmlDoc;
		try
		{
		    xmlDoc = new ActiveXObject('Microsoft.XMLDOM');
		}
		catch(e)
		{
		    try
		    {
		        xmlDoc = document.implementation.createDocument('', '', null);
		    }
		    catch(e)
		    {
		        xmlDoc = null;
		    }
		}
		return xmlDoc;
    }