// JavaScript Document

//字符串为空
function isNull(str) {
	if(str == null || str == "" || str.length < 1)
		return true;
	else
		return false;
}

//对话框消息提示
function errMsgBox(msg, ctrlName) {
	alert(msg);
	$("#" + ctrlName).focus();
}

//获取URL参数值
function getQueryString(key)
{
    var returnValue = "";
    var URLString = new String(document.location);
    var serachLocation=-1;
    var queryStringLength=key.length;
    
    do
    {
        serachLocation=URLString.indexOf(key+"\=");
        if (serachLocation!=-1)
        {
            if ((URLString.charAt(serachLocation-1)=='?') || (URLString.charAt(serachLocation-1)=='&'))
            {
                URLString=URLString.substr(serachLocation);
                break;
            }
            URLString=URLString.substr(serachLocation+queryStringLength+1);
        }
    }
    
    while (serachLocation!=-1)
        if (serachLocation!=-1)
        {
            var seperatorLocation=URLString.indexOf("&");
            if (seperatorLocation==-1)
                returnValue=URLString.substr(queryStringLength+1);
            else
                returnValue=URLString.substring(queryStringLength+1,seperatorLocation);
        }
    
    return returnValue;
}

//获取不带参数的URL
function getUrl()
{
	var url = document.location.href.toLowerCase();
	var pos = url.indexOf("?");
	if(pos > 0) url = url.substring(1, pos);
	return url;
}

//获取随机数
function getRandomNum(minNum,maxNum)
{
    return Math.floor(Math.random()*(maxNum-minNum+1))+minNum;
}

//生成Ajax随机参数
function getRnd()
{
    var mydate = new Date();
    var rnd = mydate.getHours().toString() + mydate.getMinutes().toString() + getRandomNum(1,9999).toString();
    return rnd;
}

//重置验证码
function changeCode(objName)
{
    $("#" + objName).attr("src", $("#" + objName).attr("src") + "&rnd=" + getRnd());
}

//preview image
(function($) {
    $.fn.PreviewImage = function(options) {
        var Default = {
            ImageClientId: "",
            MaxWidth: 300,
            MaxHeight: 300
        };
        $.extend(true, Default, options);
        return this.each(function() {
            if (Default.ImageClientId != "") {
                $(this).unbind("change");
                $(this).change(function() {
                    if ($(this).val() == "") {
                        $("#" + Default.ImageClientId).parent("div").hide();
                        return;
                    }
                    else {
                        $("#" + Default.ImageClientId).parent("div").show();
                    }
                    if ($.browser.msie) {
                        $("#" + Default.ImageClientId).attr("src", $(this).val());
                    }
                    else {
                        $("#" + Default.ImageClientId).attr("src", $(this)[0].files[0].getAsDataURL());
                    }
                    if ($.browser.msie && $.browser.version > 6) {
                        $("#" + Default.ImageClientId).hide();
                        $("#" + Default.ImageClientId).parent("div").css({ 'z-index': '999',
                            'filter': 'progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)',
                            'max-width': Default.MaxWidth + 'px', 'max-height': Default.MaxHeight + 'px',
                            'width': Default.MaxWidth + 'px', 'height': Default.MaxHeight + 'px',
                            'margin-bottom': '8px', 'border': '1px solid #cccccc'
                        });
                        var div = $("#" + Default.ImageClientId).parent("div")[0];
                        div.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = $("#" + Default.ImageClientId).attr("src");
                    }
                });

//                $("#" + Default.ImageClientId).load(function() {
//                    var image = new Image();
//                    image.src = $(this).attr("src");
//                    $(this).attr("width", Default.MaxWidth);
//                    $(this).attr("height", Default.MaxHeight);
//                });
            }
        });
    };
})(jQuery);