js+ajax获取文件大小

顾名思义，通过JS和Ajax来获取上传文件的大小，在上传之前可以有个判断，对上传的文件有所控制，因为js控制文件大小（JS获取文件大小）有些问题，具体大家试下就知道了，在此整理了一下ajax的获取文件大小的方法，比较好用，再调试过程中，出现了c:/fakepath/ 的错误，也将解决方案罗列在下面，以供大家参考

废话少说，代码如下

JS如下：

<script language="Jscript">
function chksize(){
     
         var ticketType = "Oil";
        var file1=document.getElementById("txtfile");
        var v = file1.value;
      
file1.select();

var realpath = document.selection.createRange().text;

      
            var input = "<Record><Type>TicketLoanResult</Type><TicketType>" + realpath + "</TicketType></Record>";

         var objXmlHttp = new ActiveXObject("Microsoft.XMLHTTP");      
         objXmlHttp.Open("POST", "XMLHttpPost.aspx", false);
         
         objXmlHttp.Send(input);
         
         var returnXml = objXmlHttp.responseText;
         if(returnXml!=null)
         {
        
            returnXml=parseInt(returnXml/1024/1024);
          
           
         }
        alert(returnXml);
       return false;
}
    </script>

后台代码：

public partial class XMLHttpPost : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            XmlDocument xmlDocumenet = new XmlDocument();

            xmlDocumenet.Load(Request.InputStream);

            string type = xmlDocumenet.SelectSingleNode("descendant::Type").InnerText;

            string returnMessage = string.Empty;

            switch (type.Trim())
            {
                case "TicketLoanResult":
                    returnMessage = GetTicketLoanResult(xmlDocumenet);
                    break;
                default:
                    break;
            }

            Response.ContentType = "text/xml";
            Response.Write(returnMessage);
        }
        catch (Exception exceptional)
        {
            //如果有錯誤則返回錯誤信息（Xml格式）
            string errorMessage = "<Error>" + exceptional.Message + "</Error>";
            Response.ContentType = "text/xml";
            Response.Write(errorMessage);
        }
        finally
        {
            Response.End();
        }
    }

    private string GetTicketLoanResult(XmlDocument input)
    {
        XmlNode item = input.SelectSingleNode("descendant::TicketType");
        string ticketType = item.InnerText.Trim();
        FileStream stream = new FileStream(ticketType,FileMode.Open);
        return stream.Length.ToString();
    }
}

整体代码下载如下：

Js+ajax 获取文件大小源代码下载

相关文章：

1、JS获取文件大小：http://www.cnblogs.com/skylaugh/archive/2012/07/05/2577702.html

 2、IE浏览器上传文件时本地路径变成”C:\fakepath\”的问题：http://www.cnblogs.com/skylaugh/archive/2012/07/05/2577736.html