UpLoadFileCheck = function()
{
    this.AllowExt = ".jpg,.jpeg"; //允许上传的文件类型 0为无限制 每个扩展名后边要加一个"," 小写字母表示 
    this.AllowImgFileSize = 0; //允许上传文件的大小 0为无限制 单位：KB 
    this.AllowImgWidth = 0; //允许上传的图片的宽度 0为无限制　单位：px(像素) 
    this.AllowImgHeight = 0; //允许上传的图片的高度 0为无限制　单位：px(像素) 
    this.ImgObj = new Image();
    this.ImgFileSize = 0;
    this.ImgWidth = 0;
    this.ImgHeight = 0;
    this.FileExt = "";
    this.ErrMsg = "";
    this.IsImg = false; //全局变量
}

UpLoadFileCheck.prototype.CheckExt = function(obj)
{
    this.ErrMsg = "";
    this.ImgObj.src = obj.value;
    //this.HasChecked=false; 	
    if (obj.value == "")
    {
        this.ErrMsg = "\n请选择一个文件";
    }
    else
    {
        this.FileExt = obj.value.substr(obj.value.lastIndexOf(".")).toLowerCase();
        if (this.AllowExt != 0 && this.AllowExt.indexOf(this.FileExt) == -1) //判断文件类型是否允许上传 
        {
            this.ErrMsg = "\n该文件类型不允许上传。请上传 " + this.AllowExt + " 类型的文件，当前文件类型为" + this.FileExt;
        }
    }
    if (this.ErrMsg != "")
    {
        this.ShowMsg(this.ErrMsg, false);
        return false;
    }
    else
    {
        return this.CheckProperty(obj);
    }
}

UpLoadFileCheck.prototype.CheckProperty = function(obj)
{
    if (this.ImgObj.readyState != "complete") //
    {
        sleep(500); //500毫秒，使图能完全加载				
    }

    if (this.IsImg == true)
    {
        this.ImgWidth = this.ImgObj.width; //取得图片的宽度 
        this.ImgHeight = this.ImgObj.height; //取得图片的高度
        if (this.AllowImgWidth != 0 && this.AllowImgWidth < this.ImgWidth) this.ErrMsg = this.ErrMsg + "\n图片宽度超过限制。请上传宽度小于" + this.AllowImgWidth + "px的文件，当前图片宽度为" + this.ImgWidth + "px";

        if (this.AllowImgHeight != 0 && this.AllowImgHeight < this.ImgHeight) this.ErrMsg = this.ErrMsg + "\n图片高度超过限制。请上传高度小于" + this.AllowImgHeight + "px的文件，当前图片高度为" + this.ImgHeight + "px";
    }

    this.ImgFileSize = Math.round(this.ImgObj.fileSize / 1024 * 100) / 100; //取得图片文件的大小 	
    if (this.AllowImgFileSize != 0 && this.AllowImgFileSize < this.ImgFileSize) this.ErrMsg = this.ErrMsg + "\n文件大小超过限制。请上传小于" + this.AllowImgFileSize + "KB的文件，当前文件大小为" + this.ImgFileSize + "KB";

    if (this.ErrMsg != "")
    {
        this.ShowMsg(this.ErrMsg, false);
        return false;
    }
    else
    {
        return true;
    }
}

UpLoadFileCheck.prototype.ShowMsg = function(msg, tf) //显示提示信息 tf=false 显示错误信息 msg-信息内容 
{
    /*msg=msg.replace("\n","<li>"); 
		msg=msg.replace(/\n/gi,"<li>"); 
		 */
    alert(msg);
}

function sleep(num)
{
    var tempDate = new Date();
    var tempStr = "";
    var theXmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    while ((new Date() - tempDate) < num)
    {
        tempStr += "\n" + (new Date() - tempDate);
        try
        {
            theXmlHttp.open("get", "about:blank?JK=" + Math.random(), false);
            theXmlHttp.send();
        }
        catch(e)
        {;
        }
    }
    //containerDiv.innerText=tempStr;   
    return;
}

function checkImg(obj, showPlace)
{
    var d = new UpLoadFileCheck();
    d.IsImg = true;
    //d.AllowImgFileSize = 100;
    d.AllowImgWidth = 800;
    d.AllowImgHeight = 800;
    
    if(d.CheckExt(obj))
    {
        var oFileChecker = document.getElementById(showPlace);
        oFileChecker.setAttribute("src", obj.value);
        oFileChecker.style.display = "block";
        if(d.ImgWidth > d.ImgHeight)
        {
            oFileChecker.style.width = "200px";
        }
        else
        {
            oFileChecker.style.height = "200px";
        }
    }
    else
    {
        var obj2= obj.cloneNode(false);
        obj2.onchange= obj.onchange; //events are not cloned 
        obj.parentNode.replaceChild(obj2,obj);

    }
}