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FileUpload Web Server Control Declarative

Creates an <input type=file> control (usually shown as a text box control and a browse button) that enables users to select a file to upload to the server.

<asp:FileUpload
    AccessKey="string"
    BackColor="color name|#dddddd"
    BorderColor="color name|#dddddd"
    BorderStyle="NotSet|None|Dotted|Dashed|Solid|Double|Groove|Ridge|
        Inset|Outset"
    BorderWidth="size"
    CssClass="string"
    Enabled="True|False"
    EnableTheming="True|False"
    EnableViewState="True|False"
    Font-Bold="True|False"
    Font-Italic="True|False"
    Font-Names="string"
    Font-Overline="True|False"
    Font-Size="string|Smaller|Larger|XX-Small|X-Small|Small|Medium|
        Large|X-Large|XX-Large"
    Font-Strikeout="True|False"
    Font-Underline="True|False"
    ForeColor="color name|#dddddd"
    Height="size"
    ID="string"
    OnDataBinding="DataBinding event handler"
    OnDisposed="Disposed event handler"
    OnInit="Init event handler"
    OnLoad="Load event handler"
    OnPreRender="PreRender event handler"
    OnUnload="Unload event handler"
    runat="server"
    SkinID="string"
    Style="string"
    TabIndex="integer"
    ToolTip="string"
    Visible="True|False"
    Width="size"
/>

Remarks

The FileUpload control displays a text box control and a browse button that allow users to select a file on the client and upload it to the Web server. The user specifies the file to upload by entering the full path to the file on the local computer (for example, C:\MyFiles\TestFile.txt) in the text box of the control. Alternatively, the user can select the file by clicking the Browse button, and then locating it in the Choose File dialog box.

The FileUpload control does not automatically send a file to the server after the user selects the file to upload. You must explicitly provide a control or mechanism to allow the user to submit the form. Typically, the file is saved or the contents handled in an event-handling method for an event that raises a post back to the server. For example, if you provide a button to submit a file, you could place the code to save the file inside the event-handling method for the click event. For more information on the FileUpload control, see FileUpload Web Server Control.

Example

The following code example demonstrates how to create a FileUpload control that saves files to a path that is specified in code. The SaveAs method is called to save the file to the specified path on the server. The ASP.NET application that includes the example must have write access to the specified directory on the server. You can explicitly grant write access to the account under which the application is running, in the directory in which the uploaded files will be saved. Alternatively, you can increase the level of trust that is granted to the ASP.NET application.

<%@ Page Language="VB" %>

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

<script runat="server">
        
  Sub UploadButton_Click(ByVal sender As Object, ByVal e As System.EventArgs)
            
    ' Specify the path on the server to
    ' save the uploaded file to.
    Dim savePath As String = "c:\temp\uploads\"
            
    ' Before attempting to perform operations
    ' on the file, verify that the FileUpload 
    ' control contains a file.
    If (FileUpload1.HasFile) Then
      ' Get the name of the file to upload.
      Dim fileName As String = FileUpload1.FileName
                      
      ' Append the name of the file to upload to the path.
      savePath += fileName
                
      ' Call the SaveAs method to save the 
      ' uploaded file to the specified path.
      ' This example does not perform all
      ' the necessary error checking.               
      ' If a file with the same name
      ' already exists in the specified path,  
      ' the uploaded file overwrites it.
      FileUpload1.SaveAs(savePath)
                
      ' Notify the user of the name the file
      ' was saved under.
      UploadStatusLabel.Text = "Your file was saved as " & fileName
                
    Else
      ' Notify the user that a file was not uploaded.
      UploadStatusLabel.Text = "You did not specify a file to upload."
    End If

  End Sub
       
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <h4>Select a file to upload:</h4>
   
       <asp:FileUpload id="FileUpload1"                 
           runat="server">
       </asp:FileUpload>
            
       <br /><br />
       
       <asp:Button id="UploadButton" 
           Text="Upload file"
           OnClick="UploadButton_Click"
           runat="server">
       </asp:Button>    
       
       <hr />
       
       <asp:Label id="UploadStatusLabel"
           runat="server">
       </asp:Label>        
    </div>
    </form>
</body>
</html>
<%@ Page Language="C#" %>

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

<script runat="server">

  protected void UploadButton_Click(object sender, EventArgs e)
  {
    // Specify the path on the server to
    // save the uploaded file to.
    String savePath = @"c:\temp\uploads\";
 
    // Before attempting to perform operations
    // on the file, verify that the FileUpload 
    // control contains a file.
    if (FileUpload1.HasFile)
    {
      // Get the name of the file to upload.
      String fileName = FileUpload1.FileName;
      
      // Append the name of the file to upload to the path.
      savePath += fileName;
      

      // Call the SaveAs method to save the 
      // uploaded file to the specified path.
      // This example does not perform all
      // the necessary error checking.               
      // If a file with the same name
      // already exists in the specified path,  
      // the uploaded file overwrites it.
      FileUpload1.SaveAs(savePath);
      
      // Notify the user of the name of the file
      // was saved under.
      UploadStatusLabel.Text = "Your file was saved as " + fileName;
    }
    else
    {      
      // Notify the user that a file was not uploaded.
      UploadStatusLabel.Text = "You did not specify a file to upload.";
    }

  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <h4>Select a file to upload:</h4>
   
       <asp:FileUpload id="FileUpload1"                 
           runat="server">
       </asp:FileUpload>
            
       <br /><br />
       
       <asp:Button id="UploadButton" 
           Text="Upload file"
           OnClick="UploadButton_Click"
           runat="server">
       </asp:Button>    
       
       <hr />
       
       <asp:Label id="UploadStatusLabel"
           runat="server">
       </asp:Label>        
    </div>
    </form>
</body>
</html>

See Also

Reference

FileUpload

Other Resources

FileUpload Web Server Control