DownloadStringCompletedEventArgs 類別

定義

命名空間:

System.Net

組件:

System.Net.WebClient.dll

來源:

WebClient.cs

提供 DownloadStringCompleted 事件的資料。

public ref class DownloadStringCompletedEventArgs : System::ComponentModel::AsyncCompletedEventArgs

public class DownloadStringCompletedEventArgs : System.ComponentModel.AsyncCompletedEventArgs

type DownloadStringCompletedEventArgs = class
    inherit AsyncCompletedEventArgs

Public Class DownloadStringCompletedEventArgs
Inherits AsyncCompletedEventArgs

繼承

Object

EventArgs

AsyncCompletedEventArgs

DownloadStringCompletedEventArgs

範例

下列程式代碼範例示範如何以異步方式下載字串。

// Sample call : DownloadStringInBackground2 ("http://www.contoso.com/GameScores.html");
void DownloadStringInBackground2( String^ address )
{
   WebClient^ client = gcnew WebClient;
   Uri ^uri = gcnew Uri(address);

   // Specify that the DownloadStringCallback2 method gets called
   // when the download completes.
   client->DownloadStringCompleted += gcnew DownloadStringCompletedEventHandler( DownloadStringCallback2 );
   client->DownloadStringAsync( uri );
}

// Sample call : DownloadStringInBackground2 ("http://www.contoso.com/GameScores.html");
public static void DownloadStringInBackground2(string address)
{
    WebClient client = new WebClient();
    Uri uri = new Uri(address);

    // Specify that the DownloadStringCallback2 method gets called
    // when the download completes.
    client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(DownloadStringCallback2);
    client.DownloadStringAsync(uri);
}

'  Sample call : DownloadStringInBackground2 ("http:' www.contoso.com/GameScores.html")
Public Shared Sub DownloadStringInBackground2(ByVal address As String)

    Dim client As WebClient = New WebClient()

    '  Specify that the DownloadStringCallback2 method gets called
    '  when the download completes.
    AddHandler client.DownloadStringCompleted, AddressOf DownloadStringCallback2
                Dim uri as Uri = New Uri(address)
    client.DownloadStringAsync(uri)
End Sub

下載完成時會呼叫下列方法。

void DownloadStringCallback2( Object^ /*sender*/, DownloadStringCompletedEventArgs^ e )
{

   // If the request was not canceled and did not throw
   // an exception, display the resource.
   if (  !e->Cancelled && e->Error == nullptr )
   {
      String^ textString = dynamic_cast<String^>(e->Result);
      Console::WriteLine( textString );
   }
}

private static void DownloadStringCallback2(Object sender, DownloadStringCompletedEventArgs e)
{
    // If the request was not canceled and did not throw
    // an exception, display the resource.
    if (!e.Cancelled && e.Error == null)
    {
        string textString = (string)e.Result;

        Console.WriteLine(textString);
    }
}

Private Shared Sub DownloadStringCallback2(ByVal sender As Object, ByVal e As DownloadStringCompletedEventArgs)

    '  If the request was not canceled and did not throw
    '  an exception, display the resource.
    If e.Cancelled = False AndAlso e.Error Is Nothing Then

        Dim textString As String = CStr(e.Result)
        Console.WriteLine(textString)
    End If
End Sub

備註

這個類別的實體會傳遞至 DownloadStringCompletedEventHandler。

屬性

Cancelled	取得值，指出非同步作業是否已取消。 (繼承來源 AsyncCompletedEventArgs)
Error	取得值，指出非同步作業期間是否發生錯誤。 (繼承來源 AsyncCompletedEventArgs)
Result	取得 DownloadStringAsync 方法所下載的資料。
UserState	取得非同步工作的唯一識別項。 (繼承來源 AsyncCompletedEventArgs)

方法

Equals(Object)	判斷指定的物件是否等於目前的物件。 (繼承來源 Object)
GetHashCode()	做為預設雜湊函式。 (繼承來源 Object)
GetType()	取得目前執行個體的 Type。 (繼承來源 Object)
MemberwiseClone()	建立目前 Object 的淺層複製。 (繼承來源 Object)
RaiseExceptionIfNecessary()	如果非同步作業失敗，引發使用者提供的例外狀況。 (繼承來源 AsyncCompletedEventArgs)
ToString()	傳回代表目前物件的字串。 (繼承來源 Object)