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Per l'upload in asp.net

fileupload.aspx
codice:
<%@ Page Language="C#" AutoEventWireup="True" Debug="true"%>
<%@ Import Namespace="System.IO" %>

<script Language="C#" runat="server">

protected void SubmitButton_Click(Object sender, EventArgs e)
 {
  string filepath = Server.MapPath("/" + "Downloads") + "\\";
  string fileName = "";

  HttpFileCollection uploadedFiles = Request.Files;
  Span1.InnerHtml = "";

  for (int i = 0; i < uploadedFiles.Count; i++)
   {    
    HttpPostedFile userPostedFile = uploadedFiles[i];
  
	try
     {    
      if (userPostedFile.ContentLength > 0 )
       {
	    fileName = Path.GetFileName(userPostedFile.FileName);
		Span1.InnerHtml += "<u>File #" + (i+1) + "</u>
";
		Span1.InnerHtml += "File Content Type: " + userPostedFile.ContentType + "
";
		
		if (userPostedFile.ContentLength > 1024)
		 {
		  Span1.InnerHtml += "File Size: " + ((double)(userPostedFile.ContentLength) / 1024.0).ToString("N3") + " kb
";
		 }
		else
		 {
		  Span1.InnerHtml += "File Size: " + userPostedFile.ContentLength + " bytes
";
		 }
		Span1.InnerHtml += "File Name: " + userPostedFile.FileName + "
";
		userPostedFile.SaveAs(filepath + "\\" + Path.GetFileName(userPostedFile.FileName));
		Span1.InnerHtml += "Location where saved: " + filepath + "\\" + Path.GetFileName(userPostedFile.FileName) + "

";
       } // if (userPostedFile.ContentLength > 0 )
      } 
     catch (Exception Ex)
      {    
       Span1.InnerText += "Error: 
" + Ex.Message;    
      }    
   }    
 }
</script>

<html>
  <head>
  </head>
 <body>
  Back to Index
  <form enctype="multipart/form-data" runat="server"></br>
    Select File1:

    <input id="File1" type="file" runat="Server"/>

    Select File2:

    <input id="File2" type="file" runat="Server"/>

    Select File3:

    <input id="File3" type="file" runat="Server"/>

    Select File4:

    <input id="File4" type="file" runat="Server"/>

    Select File5:

    <input id="File5" type="file" runat="Server"/>

    Select File6:

    <input id="File6" type="file" runat="Server"/>

    Select File7:

    <input id="File7" type="file" runat="Server"/>

    Select File8:

    <input id="File8" type="file" runat="Server"/>

    Select File9:

    <input id="File9" type="file" runat="Server"/>

    Select File10:

    <input id="File10" type="file" runat="Server"/>

    Select File11:

    <input id="File11" type="file" runat="Server"/>

    Select File12:

    <input id="File12" type="file" runat="Server"/>

    Select File13:

    <input id="File13" type="file" runat="Server"/>

    Select File14:

    <input id="File14" type="file" runat="Server"/>

    Select File15:

    <input id="File15" type="file" runat="Server"/>


    <input id="Submit1" type="submit" value="Upload Files" runat="Server" onserverclick="SubmitButton_Click"/>


    <span id="Span1" runat="Server"></span>
  </form>
  Back to Index
 </body>
</html>