ASP. NET breakpoint continued to pass

Using System;    Using System.Data;    Using System.Configuration;    Using System.Collections;    Using System.Web;    Using System.Web.Security;    Using System.Web.UI;    Using System.Web.UI.WebControls;    Using System.Web.UI.WebControls.WebParts;    Using System.Web.UI.HtmlControls;    Using System.IO;    Public partial class DFile:System.Web.UI.Page {protected void Page_Load (object sender, EventArgs e) {}    protected void Linbtndfile_click (object sender, EventArgs e) {//Create a bit array byte[] buffer = new byte[10240];    Specifies the path to the file to download.    String filePath = @ "D:\-ji-ai-nook. rar";    Or take the file name including the extension string filename = Path.getfilename (FilePath);    Stream fileStream = null;    try {//Open file FileStream = new FileStream (FilePath, FileMode.Open, FileAccess.Read, FileShare.Read);    Response.Clear ();    Gets the size of the file long fileSize = Filestream.length;    Long sum = 0; if (request.headers["Range"] = null) {Response.statuscode = 206;//indicates the HTTP output to return to the clientThe integer of the state.    The default value is 200. sum = long. Parse (request.headers["Range"). Replace ("bytes=", "").    Replace ("-", "")); } if (sum! = 0) {Response.AddHeader ("content-range", "bytes" + sum.) ToString () + "-" + ((long) (fileSize)).    ToString () + "/" + filesize.tostring ()); }//Get some HTTP header information Response.AddHeader ("Content-length", ((Long) (Filesize-sum)).    ToString ());    Response.ContentType = "Application/octet-stream"; Get the file source Response.AddHeader ("content-disposition", "attachment;    Filename= "+ Httputility.urlencode (Request.ContentEncoding.GetBytes (fileName));    Response.Flush (); filestream.position = sum;    Sets the current stream position fileSize = filesize-sum; When the file size is greater than 0 is entered into the loop while (FileSize > 0) {//Determines whether the client is still connected in the server if (response.isclientconnected) {//Get buffer    The total number of bytes.    int length = filestream.read (buffer, 0, 10240);    Write Data Response.OutputStream.Write (buffer, 0, length);    Sends the output of the buffer to the client Response.Flush ();    Buffer = new byte[10240]; FileSize = FileSize- Length    } else {//when the user disconnects and exits the loop fileSize =-1; }}} catch (Exception ex) {Response.Write ("Error:" + ex.)    Message);    } finally {if (FileStream! = null) {//Close file Filestream.close ();    } response.end (); }    }    }

　　

ASP. NET breakpoint continued to pass