FileUpload.FileContent Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee haalt u een Stream object op dat naar een bestand verwijst om te uploaden met behulp van het FileUpload besturingselement.
public:
property System::IO::Stream ^ FileContent { System::IO::Stream ^ get(); };[System.ComponentModel.Browsable(false)]
public System.IO.Stream FileContent { get; }[<System.ComponentModel.Browsable(false)>]
member this.FileContent : System.IO.StreamPublic ReadOnly Property FileContent As StreamWaarde van eigenschap
Een Stream bestand dat verwijst naar een bestand dat moet worden geüpload met behulp van de FileUpload.
- Kenmerken
Voorbeelden
In het volgende voorbeeld ziet u hoe u een FileUpload besturingselement maakt. De FileContent eigenschap wordt gebruikt om de inhoud van het bestand te lezen in een bytematrix. Wanneer de gebruiker op de knop Bestand uploaden klikt, wordt de inhoud van het bestand weergegeven als bytes in een tekstvak op de pagina.
<%@ 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)
{
// Append the name of the file to upload to the path.
savePath += FileUpload1.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 that the file was uploaded successfully.
UploadStatusLabel.Text = "Your file was uploaded successfully.";
// Call a helper routine to display the contents
// of the file to upload.
DisplayFileContents(FileUpload1.PostedFile);
}
else
{
// Notify the user that a file was not uploaded.
UploadStatusLabel.Text = "You did not specify a file to upload.";
}
}
void DisplayFileContents(HttpPostedFile file)
{
System.IO.Stream myStream;
Int32 fileLen;
StringBuilder displayString = new StringBuilder();
// Get the length of the file.
fileLen = FileUpload1.PostedFile.ContentLength;
// Display the length of the file in a label.
LengthLabel.Text = "The length of the file is " +
fileLen.ToString() + " bytes.";
// Create a byte array to hold the contents of the file.
Byte[] Input = new Byte[fileLen];
// Initialize the stream to read the uploaded file.
myStream = FileUpload1.FileContent;
// Read the file into the byte array.
myStream.Read(Input, 0, fileLen);
// Copy the byte array to a string.
for (int loop1 = 0; loop1 < fileLen; loop1++)
{
displayString.Append(Input[loop1].ToString());
}
// Display the contents of the file in a
// textbox on the page.
ContentsLabel.Text = "The contents of the file as bytes:";
TextBox ContentsTextBox = new TextBox();
ContentsTextBox.TextMode = TextBoxMode.MultiLine;
ContentsTextBox.Height = Unit.Pixel(300);
ContentsTextBox.Width = Unit.Pixel(400);
ContentsTextBox.Text = displayString.ToString();
// Add the textbox to the Controls collection
// of the Placeholder control.
PlaceHolder1.Controls.Add(ContentsTextBox);
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FileUpload.FileContent Property 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>
<br /><br />
<asp:Label id="UploadStatusLabel"
runat="server">
</asp:Label>
<hr />
<asp:Label id="LengthLabel"
runat="server">
</asp:Label>
<br /><br />
<asp:Label id="ContentsLabel"
runat="server">
</asp:Label>
<br /><br />
<asp:PlaceHolder id="PlaceHolder1"
runat="server">
</asp:PlaceHolder>
</div>
</form>
</body>
</html>
<%@ 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
' Append the name of the file to upload to the path.
savePath += FileUpload1.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 that the file was uploaded successfully.
UploadStatusLabel.Text = "Your file was uploaded successfully."
' Call a helper routine to display the contents
' of the file to upload.
DisplayFileContents(FileUpload1.PostedFile)
Else
' Notify the user that a file was not uploaded.
UploadStatusLabel.Text = "You did not specify a file to upload."
End If
End Sub
Sub DisplayFileContents(ByVal file As HttpPostedFile)
Dim myStream As System.IO.Stream
Dim fileLen As Integer
Dim displayString As New StringBuilder()
Dim loop1 As Integer
' Get the length of the file.
fileLen = FileUpload1.PostedFile.ContentLength
' Display the length of the file in a label.
LengthLabel.Text = "The length of the file is " _
+ fileLen.ToString + " bytes."
' Create a byte array to hold the contents of the file.
Dim Input(fileLen) As Byte
' Initialize the stream to read the uploaded file.
myStream = FileUpload1.FileContent
' Read the file into the byte array.
myStream.Read(Input, 0, fileLen)
' Copy the byte array to a string.
For loop1 = 0 To fileLen - 1
displayString.Append(Input(loop1).ToString())
Next loop1
' Display the contents of the file in a
' textbox on the page.
ContentsLabel.Text = "The contents of the file as bytes:"
Dim ContentsTextBox As New TextBox
ContentsTextBox.TextMode = TextBoxMode.MultiLine
ContentsTextBox.Height = Unit.Pixel(300)
ContentsTextBox.Width = Unit.Pixel(400)
ContentsTextBox.Text = displayString.ToString()
' Add the textbox to the Controls collection
' of the Placeholder control.
PlaceHolder1.Controls.Add(ContentsTextBox)
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FileUpload.FileContent Property 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>
<br /><br />
<asp:Label id="UploadStatusLabel"
runat="server">
</asp:Label>
<hr />
<asp:Label id="LengthLabel"
runat="server">
</asp:Label>
<br /><br />
<asp:Label id="ContentsLabel"
runat="server">
</asp:Label>
<br /><br />
<asp:PlaceHolder id="PlaceHolder1"
runat="server">
</asp:PlaceHolder>
</div>
</form>
</body>
</html>
Opmerkingen
De FileContent eigenschap haalt een Stream object op dat verwijst naar een bestand dat moet worden geüpload met behulp van het FileUpload besturingselement. Gebruik de FileContent eigenschap voor toegang tot de inhoud van het bestand. U kunt bijvoorbeeld het Stream object gebruiken dat door deze eigenschap wordt geretourneerd om de inhoud van het bestand als bytes te lezen en op te slaan in een bytematrix.
