FileUpload Web 伺服器控制項宣告式語法
更新：2007 年 11 月
建立可讓使用者選取要上載至伺服器之檔案的 <input type=file> 控制項 (通常顯示為文字方塊控制項和瀏覽按鈕)。
<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"
/>
備註
FileUpload 控制項會顯示文字方塊控制項和瀏覽按鈕，該控制項和按鈕可允許使用者選取用戶端上的檔案並將其上載至 Web 伺服器。使用者可藉由在控制項的文字方塊中輸入本機電腦上檔案的完整路徑 (例如，C:\MyFiles\TestFile.txt) 來指定要上載的檔案。或者，使用者也可以選取檔案，方法即按一下 [瀏覽] 按鈕，然後在 [選擇檔案] 對話方塊中尋找檔案。
在使用者選取要上載的檔案之後，FileUpload 控制項不會自動將檔案傳送至伺服器。您必須明確地提供控制項或機制，讓使用者送出表單。通常，在引發回傳至伺服器之事件的事件處理方法中儲存檔案或處理內容。例如，如果您提供送出檔案的按鈕，則可以將儲存檔案的程式碼置於按一下事件的事件處理方法中。如需 FileUpload 控制項的詳細資訊，請參閱 HOW TO：以 FileUpload Web 伺服器控制項上載檔案。
範例
在下列程式碼範例中，會示範如何建立 FileUpload 控制項，該控制項可將檔案儲存至程式碼中指定的路徑。此控制項會呼叫 SaveAs 方法，以將檔案儲存至伺服器上的指定路徑。含有範例的 ASP.NET 應用程式必須具有伺服器上指定目錄的寫入權限。您可以明確將寫入權限授與應用程式執行時所用的帳戶 (在要儲存上載之檔案的目錄中)。或者，您可以增加授與 ASP.NET 應用程式的信任層級。
<%@ 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>