Question

我正在尝试使用AJAX上传文件问题是我是.net中的新手而且不知道我是否做得对，所以我感谢任何帮助或建议。

这是我的HTML代码：

<asp:FileUpload ID="FileUpload1" onChange="Show()" runat="server" />

用户选择文件时应调用我的方法

这是我在MSDN中找到的脚本：

<script type="text/javascript">
    function Show() {
        var file = document.getElementById("FileUpload1");
        alert("test")
        $.ajax({
            type: "POST",
            url: "SendSms.aspx/StaticUpdate",
            data: '{name:"test" }',
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: OnSuccess,
            failure: function (response) {
                alert("test1");
            }
        });
    }
    function OnSuccess(response) {
        alert("test2");
    }
</script>

这是我的ASP方法：

    [System.Web.Services.WebMethod]
public static void StaticUpdate()
{
    SendSms upload = new SendSms();
    upload.Upload();
}

public void Upload()
{
    string FileName = System.DateTime.Now.ToString("ddmmyyhhmmsss") + FileUpload1.FileName;
    if (IsPostBack)
    {
        Boolean fileOK = false;
        String path = Server.MapPath("~/Upload/");
        if (FileUpload1.HasFile)
        {
            String fileExtension =
                System.IO.Path.GetExtension(FileName).ToLower();
            String[] allowedExtensions = { ".txt" };
            for (int i = 0; i < allowedExtensions.Length; i++)
            {
                if (fileExtension == allowedExtensions[i])
                {
                    fileOK = true;
                }
            }
        }
        if (fileOK)
        {
            try
            {
                FileUpload1.PostedFile.SaveAs(path
                    + FileName);
                System.IO.StreamReader myFile =
new System.IO.StreamReader("C:\\inetpub\\wwwroot\\Viber_Bulk_UI\\Upload\\" + FileName + "");
                TextBox2.Text = myFile.ReadToEnd();
                myFile.Close();
                string Path = "C:\\inetpub\\wwwroot\\Viber_Bulk_UI\\Upload\\" + FileName + "";
                System.IO.File.Delete(Path);
            }
            catch (Exception ex)
            {
                Label1.Text = "File could not be uploaded.";
            }
        }
        else
        {
            Label1.Text = "Cannot accept files of this type.";
        }
    }

}

我得到的错误是：

NullReferenceException未被用户代码处理。对象引用未设置为对象的实例。

提前致谢

Answer 1

 string filename = System.IO.Path.GetFileName(FileUpload1.FileName);
 string ext = System.IO.Path.GetExtension(FileUpload1.FileName);
 if (fileExtension == ".txt"){

           using (System.IO.FileStream fs = new System.IO.FileStream(Server.MapPath(("C:\\inetpub\\wwwroot\\Viber_Bulk_UI\\Upload\\" + FileName), System.IO.FileMode.Append, System.IO.FileAccess.Write, System.IO.FileShare.Read, 8, System.IO.FileOptions.None))
        {
            byte[] data = System.Text.Encoding.ASCII.GetBytes(FileName);
            fs.Write(data, 0, data.Length);
            fs.Flush();
            fs.Close();
        }
  }

如何在文件上载更改中调用AJAX中的.net方法？

1 个答案: