HttpResponse.WriteFile Method (IntPtr, Int64, Int64)
Writes the specified file directly to an HTTP response output stream.
Assembly: System.Web (in System.Web.dll)
<SecurityPermissionAttribute(SecurityAction.Demand, UnmanagedCode := True)> Public Sub WriteFile ( fileHandle As IntPtr, offset As Long, size As Long )
When this method is used with large files, calling the method might throw an exception. The size of the file that can be used with this method depends on the hardware configuration of the Web server. For more information, see article 812406, "PRB: Response.WriteFile Cannot Download a Large File" on the Microsoft Knowledge Base Web site.
The following example writes all the contents of a text file named Login.txt (which might contain literal HTML text and input controls) directly to the output stream.
Dim FileName As String Dim MyFileStream As FileStream Dim FileHandle As IntPtr Dim StartPos As Long = 0 Dim FileSize As Long FileName = "c:\\temp\\Login.txt" MyFileStream = New FileStream(FileName, FileMode.Open) FileHandle = MyFileStream.Handle FileSize = MyFileStream.Length Response.Write("<b>Login: </b>") Response.Write("<input type=text id=user /> ") Response.Write("<input type=submit value=Submit /><br><br>") Response.WriteFile(FileHandle, StartPos, FileSize) MyFileStream.Close()
Available since 1.1