UploadFileCompletedEventHandler 代理人

定義

命名空間:

System.Net

組件:

netstandard.dll, System.Net.WebClient.dll

來源:

WebClient.cs

代表將處理 UploadFileCompleted 之 WebClient 事件的方法。

public delegate void UploadFileCompletedEventHandler(System::Object ^ sender, UploadFileCompletedEventArgs ^ e);

public delegate void UploadFileCompletedEventHandler(object sender, UploadFileCompletedEventArgs e);

type UploadFileCompletedEventHandler = delegate of obj * UploadFileCompletedEventArgs -> unit

Public Delegate Sub UploadFileCompletedEventHandler(sender As Object, e As UploadFileCompletedEventArgs)

參數

sender

Object

事件的來源。

e

UploadFileCompletedEventArgs

包含事件資料的 UploadFileCompletedEventArgs。

範例

下列程式代碼範例示範如何以異步方式上傳檔案。

// Sample call: UploadFileInBackground("http://www.contoso.com/fileUpload.aspx", "data.txt")
public static void UploadFileInBackground(string address, string fileName)
{
    System.Threading.AutoResetEvent waiter = new System.Threading.AutoResetEvent(false);
    WebClient client = new WebClient();
    Uri uri = new Uri(address);
    string method = "POST";

    // Specify that that UploadFileCallback method gets called
    // when the file upload completes.
    client.UploadFileCompleted += new UploadFileCompletedEventHandler(UploadFileCallback);
    client.UploadFileAsync(uri, method, fileName, waiter);

    // Block the main application thread. Real applications
    // can perform other tasks while waiting for the upload to complete.
    waiter.WaitOne();
    Console.WriteLine("File upload is complete.");
}

'  Sample call: UploadFileInBackground("http:' www.contoso.com/fileUpload.aspx", "data.txt")
Public Shared Sub UploadFileInBackground(ByVal address As String, ByVal fileName As String)

    Dim waiter As System.Threading.AutoResetEvent = New System.Threading.AutoResetEvent(False)
    Dim client As WebClient = New WebClient()
    Dim method As String = "POST"
                 Dim uri as Uri =  New Uri(address)

    '  Specify that that UploadFileCallback method gets called
    '  when the file upload completes.
    AddHandler client.UploadFileCompleted, AddressOf UploadFileCallback
    client.UploadFileAsync(uri, method, fileName, waiter)

    '  Block the main application thread. Real applications
    '  can perform other tasks while waiting for the upload to complete.
    waiter.WaitOne()
    Console.WriteLine("File upload is complete.")
End Sub

上傳完成時會呼叫下列方法。

private static void UploadFileCallback(Object sender, UploadFileCompletedEventArgs e)
{
    System.Threading.AutoResetEvent waiter = (System.Threading.AutoResetEvent)e.UserState; ;
    try
    {
        string reply = System.Text.Encoding.UTF8.GetString(e.Result);

        Console.WriteLine(reply);
    }
    finally
    {
        // If this thread throws an exception, make sure that
        // you let the main application thread resume.
        waiter.Set();
    }
}

Private Shared Sub UploadFileCallback(ByVal sender As Object, ByVal e As System.Net.UploadFileCompletedEventArgs)

    Dim waiter As System.Threading.AutoResetEvent = CType(e.UserState, System.Threading.AutoResetEvent)
    Try

        Dim reply As String = System.Text.Encoding.UTF8.GetString(e.Result)
        Console.WriteLine(reply)
    Finally
        '  If this thread throws an exception, make sure that
        '  you let the main application thread resume.
        waiter.Set()
    End Try
End Sub

備註

建立 UploadFileCompletedEventHandler 委派時，必須識別處理事件的方法。 若要使事件與您的事件處理常式產生關聯，請將委派的執行個體 (Instance) 加入至事件。 除非您移除委派，否則每當事件發生時就會呼叫事件處理常式。 如需事件處理程式委派的詳細資訊，請參閱 處理和引發事件。

擴充方法

名稱	Description
GetMethodInfo(Delegate)	取得表示特定委派所代表之方法的物件。