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HtmlInputFile.PostedFile Property

  • Reference

Definition

Namespace:
System.Web.UI.HtmlControls
Assembly:
System.Web.dll

Gets access to the uploaded file specified by a client.

public:
 property System::Web::HttpPostedFile ^ PostedFile { System::Web::HttpPostedFile ^ get(); };
public System.Web.HttpPostedFile PostedFile { get; }
member this.PostedFile : System.Web.HttpPostedFile
Public ReadOnly Property PostedFile As HttpPostedFile

Property Value

HttpPostedFile

A HttpPostedFile that accesses the file to be uploaded.

Examples

The following code example demonstrates how to use the PostedFile property to initiate the utility that transfers the file to the server. Note that if the size of the uploaded file in bytes exceeds the value of the ContentLength property, the file is not uploaded. For this example to work properly, you need to create a directory called Temp on your computer's drive C.

<%@ Page Language="C#" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void Button1_Click(object Source, EventArgs e)
  {

    // Make sure a file was submitted.
    if (Text1.Value == "")
    {
      
      Span1.InnerHtml = "Error: You must enter a file name.";
      return;
      
    }

    // Save the file.
    if (File1.PostedFile.ContentLength > 0)
    {
      try
      {
        
        File1.PostedFile.SaveAs("c:\\temp\\" + Text1.Value);
        Span1.InnerHtml = "File uploaded successfully to <b>c:\\temp\\" +
                           Text1.Value + "</b> on the Web server.";
        
      }
      catch (Exception exc)
      {
        
        Span1.InnerHtml = "Error saving file <b>c:\\temp\\" +
                           Text1.Value + "</b><br />" + exc.ToString() + ".";
        
      }
      
    }
    
  }
 
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>HtmlInputFile Example</title>
  </head>
 
  <body>
 
    <h3>HtmlInputFile Example</h3>
 
    <form id="form1" enctype="multipart/form-data" 
          runat="server">
 
       Select File to Upload: 
       <input id="File1" 
              type="file"
              runat="server"/>
 
       <p>
       Save as file name (no path): 
       <input id="Text1" 
              type="text" 
              runat="server"/>
 
       </p>
       <p>
       <span id="Span1" 
             style="font: 8pt verdana;" 
             runat="server" />
 
       </p>
       <p>
       <input type="button" 
              id="Button1" 
              value="Upload" 
              onserverclick="Button1_Click" 
              runat="server" />

       </p>

    </form>
 
  </body>
</html>

<%@ Page Language="VB" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub Button1_Click(ByVal Source As Object, ByVal e As EventArgs)
        
    ' Make sure a file was submitted.
    If Text1.Value = "" Then
      
      Span1.InnerHtml = "Error: You must enter a file name."
      Return
      
    End If
        
    ' Save the file.
    If File1.PostedFile.ContentLength > 0 Then
      Try
        
        File1.PostedFile.SaveAs(("c:\temp\" & Text1.Value))
        Span1.InnerHtml = "File uploaded successfully to <b>c:\temp\" & _
                           Text1.Value & "</b> on the Web server."
        
      Catch exc As Exception
        
        Span1.InnerHtml = "Error saving file <b>c:\temp\" & _
                           Text1.Value & "</b><br />" & exc.ToString() + "."
        
      End Try
      
    End If
    
  End Sub
 
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>HtmlInputFile Example</title>
  </head>
 
  <body>
 
    <h3>HtmlInputFile Example</h3>
 
    <form id="form1" enctype="multipart/form-data" 
          runat="server">
 
       Select File to Upload: 
       <input id="File1" 
              type="file"
              runat="server"/>
 
       <p>
       Save as file name (no path): 
       <input id="Text1" 
              type="text" 
              runat="server"/>
 
       </p>
       <p>
       <span id="Span1" 
             style="font: 8pt verdana;" 
             runat="server" />
 
       </p>
       <p>
       <input type="button" 
              id="Button1" 
              value="Upload" 
              onserverclick="Button1_Click" 
              runat="server" />

       </p>

    </form>
 
  </body>
</html>

Remarks

Browser security restrictions prevent this value from being maintained across multiple requests.

Applies to

See also