FileWebRequest 類別

  • 參考

定義

命名空間:
System.Net
組件:
System.Net.Requests.dll
組件:
System.dll
組件:
netstandard.dll

提供 WebRequest 類別的檔案系統實作。

public ref class FileWebRequest : System::Net::WebRequest, System::Runtime::Serialization::ISerializable
public ref class FileWebRequest : System::Net::WebRequest
public class FileWebRequest : System.Net.WebRequest, System.Runtime.Serialization.ISerializable
[System.Serializable]
public class FileWebRequest : System.Net.WebRequest, System.Runtime.Serialization.ISerializable
public class FileWebRequest : System.Net.WebRequest
type FileWebRequest = class
    inherit WebRequest
    interface ISerializable
[<System.Serializable>]
type FileWebRequest = class
    inherit WebRequest
    interface ISerializable
Public Class FileWebRequest
Inherits WebRequest
Implements ISerializable
Public Class FileWebRequest
Inherits WebRequest
繼承
Object
MarshalByRefObject
WebRequest
FileWebRequest
屬性
SerializableAttribute
實作
ISerializable

範例

下列程式碼範例會 FileWebRequest 使用 類別來存取檔案系統資源。

// This program creates or open a text file in which it stores a string.
// Both file and string are passed by the user.
// Note. In order for this program to work, the folder containing the test file
// must be shared with its permissions set to allow write access.
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Text;
using namespace System::Net;
ref class TestGetRequestStream
{
private:
   static FileWebRequest^ myFileWebRequest;
   static void showUsage()
   {
      Console::WriteLine( "\nPlease enter file name and timeout :" );
      Console::WriteLine( "Usage: cs_getrequeststream <systemname>/<sharedfoldername>/<filename> timeout" );
      Console::WriteLine( "Example: cs_getrequeststream ndpue/temp/hello.txt 1000" );
      Console::WriteLine( "Small timeout values (for instance 3 or less) cause a timeout exception." );
   }

   static void makeFileRequest( String^ fileName, int timeout )
   {
      try
      {
         
         // Create a Uri object.
         Uri^ myUrl = gcnew Uri( String::Format( "file://{0}", fileName ) );
         
         // Create a FileWebRequest object.
         myFileWebRequest = dynamic_cast<FileWebRequest^>(WebRequest::CreateDefault( myUrl ));
         
         // Set the timeout to the value selected by the user.
         myFileWebRequest->Timeout = timeout;
         
         // Set the Method property to POST
         myFileWebRequest->Method = "POST";
         
      }
      catch ( WebException^ e ) 
      {
         Console::WriteLine( "WebException: {0}", e->Message );
      }
      catch ( UriFormatException^ e ) 
      {
         Console::WriteLine( "UriFormatWebException: {0}", e->Message );
      }

   }

   static void writeToFile()
   {
      try
      {
         
         // Enter the string to write into the file.
         Console::WriteLine( "Enter the string you want to write:" );
         String^ userInput = Console::ReadLine();
         
         // Convert the string to Byte array.
         ASCIIEncoding^ encoder = gcnew ASCIIEncoding;
         array<Byte>^byteArray = encoder->GetBytes( userInput );
         
         // Set the ContentLength property.
         myFileWebRequest->ContentLength = byteArray->Length;
         String^ contentLength = myFileWebRequest->ContentLength.ToString();
         Console::WriteLine( "\nThe content length is {0}.", contentLength );
         
         // Get the file stream handler to write into the file.
         Stream^ readStream = myFileWebRequest->GetRequestStream();
         
         // Write to the file stream.
         // Note. In order for this to work the file must be accessible
         // on the network. This can be accomplished by setting the property
         // sharing of the folder containg the file. The permissions
         // can be set so everyone can modify the file.
         // FileWebRequest::Credentials property cannot be used for this purpose.
         readStream->Write( byteArray, 0, userInput->Length );
         Console::WriteLine( "\nThe String you entered was successfully written into the file." );
         
         readStream->Close();
      }
      catch ( WebException^ e ) 
      {
         Console::WriteLine( "The WebException: {0}", e->Message );
      }
      catch ( UriFormatException^ e ) 
      {
         Console::WriteLine( "The UriFormatWebException: {0}", e->Message );
      }

   }


public:
   static void Main()
   {
      array<String^>^args = Environment::GetCommandLineArgs();
      if ( args->Length < 3 )
            showUsage();
      else
      {
         makeFileRequest( args[ 1 ], Int32::Parse( args[ 2 ] ) );
         writeToFile();
      }
   }

};

int main()
{
   TestGetRequestStream::Main();
}

// This example creates or opens a text file and stores a string in it.
// Both the file and the string are passed by the user.
// Note. For this program to work, the folder containing the test file
// must be shared, with its permissions set to allow write access.
using System.Net;
using System;
using System.IO;
using System.Text;

namespace Mssc.PluggableProtocols.File
{
    class TestGetRequestStream
    {
        private static FileWebRequest myFileWebRequest;

        private static void showUsage ()
        {
            Console.WriteLine ("\nPlease enter file name and timeout :");
            Console.WriteLine ("Usage: cs_getrequeststream <systemname>/<sharedfoldername>/<filename> timeout");
            Console.WriteLine ("Example: cs_getrequeststream ngetrequestrtream() ndpue/temp/hello.txt  1000");
            Console.WriteLine ("Small time-out values (for example, 3 or less) cause a time-out exception.");
        }

        private static void makeFileRequest (string fileName, int timeout)
        {
            try
            {
                // Create a Uri object.
                Uri myUrl = new Uri ("file://" + fileName);

                // Create a FileWebRequest object.
                myFileWebRequest = (FileWebRequest)WebRequest.CreateDefault (myUrl);

                // Set the time-out to the value selected by the user.
                myFileWebRequest.Timeout = timeout;

                // Set the Method property to POST
                myFileWebRequest.Method = "POST";
            }
            catch (WebException e)
            {
                Console.WriteLine ("WebException: " + e.Message);
            }
            catch (UriFormatException e)
            {
                Console.WriteLine ("UriFormatWebException: " + e.Message);
            }
        }

        private static void writeToFile ()
        {
            try
            {
                // Enter the string to write to the file.
                Console.WriteLine ("Enter the string you want to write:");

                string userInput = Console.ReadLine ();

                // Convert the string to a byte array.
                ASCIIEncoding encoder = new ASCIIEncoding ();
                byte[] byteArray = encoder.GetBytes (userInput);

                // Set the ContentLength property.
                myFileWebRequest.ContentLength = byteArray.Length;

                string contentLength = myFileWebRequest.ContentLength.ToString ();

                Console.WriteLine ("\nThe content length is {0}.", contentLength);

                // Get the file stream handler to write to the file.
                Stream readStream = myFileWebRequest.GetRequestStream ();

                // Write to the file stream.
                // Note.  For this to work, the file must be accessible
                // on the network. This can be accomplished by setting the property
                // sharing of the folder containg the file.
                // FileWebRequest.Credentials property cannot be used for this purpose.
                readStream.Write (byteArray, 0, userInput.Length);
                Console.WriteLine ("\nThe String you entered was successfully written to the file.");

                readStream.Close ();
            }
            catch (WebException e)
            {
                Console.WriteLine ("The WebException: " + e.Message);
            }
            catch (UriFormatException e)
            {
                Console.WriteLine ("The UriFormatWebException: " + e.Message);
            }
        }

        public static void Main (String[] args)
        {
            if (args.Length < 2)
            {
                showUsage ();
            }
            else
            {
                makeFileRequest (args[0], int.Parse (args[1]));
                writeToFile ();
            }
        }
    }
}

'
' This example creates or opens a text file and stores a string in it. 
' Both the file and the string are passed by the user.
' Note. For this program to work, the folder containing the test file
' must be shared, with its permissions set to allow write access. 

Imports System.Net
Imports System.IO
Imports System.Text

Namespace Mssc.PluggableProtocols.File

    Module TestGetRequestStream

        Class TestGetRequestStream

            Private Shared myFileWebRequest As FileWebRequest

            ' Show how to use this program.
            Private Shared Sub showUsage()
                Console.WriteLine(ControlChars.Lf + "Please enter file name and timeout :")
                Console.WriteLine("Usage: vb_getrequeststream <systemname>/<sharedfoldername>/<filename> timeout")
                Console.WriteLine("Example: vb_getrequeststream ngetrequestrtream() ndpue/temp/hello.txt  1000")
                Console.WriteLine("Small time-out values (for example, 3 or less) cause a time-out exception.")
            End Sub

            Private Shared Sub makeFileRequest(ByVal fileName As String, ByVal timeout As Integer)
                Try
                    ' Create a Uri object.to access the file requested by the user. 
                    Dim myUrl As New Uri("file://" + fileName)

                    ' Create a FileWebRequest object.for the requeste file.
                    myFileWebRequest = CType(WebRequest.CreateDefault(myUrl), FileWebRequest)

                    ' Set the time-out to the value selected by the user.
                    myFileWebRequest.Timeout = timeout

                    ' Set the Method property to POST  
                    myFileWebRequest.Method = "POST"


                Catch e As WebException
                    Console.WriteLine(("WebException is: " + e.Message))
                Catch e As UriFormatException
                    Console.WriteLine(("UriFormatWebException is: " + e.Message))
                End Try

            End Sub

            Private Shared Sub writeToFile()
                Try
                    ' Enter the string to write to the file.
                    Console.WriteLine("Enter the string you want to write:")
                    Dim userInput As String = Console.ReadLine()

                    ' Convert the string to a byte array.
                    Dim encoder As New ASCIIEncoding
                    Dim byteArray As Byte() = encoder.GetBytes(userInput)

                    ' Set the ContentLength property.
                    myFileWebRequest.ContentLength = byteArray.Length

                    Dim contentLength As String = myFileWebRequest.ContentLength.ToString()

                    Console.WriteLine(ControlChars.Lf + "The content length is {0}.", contentLength)


                    ' Get the file stream handler to write to the file.
                    Dim readStream As Stream = myFileWebRequest.GetRequestStream()

                    ' Write to the stream. 
                    ' Note. For this to work the file must be accessible
                    ' on the network. This can be accomplished by setting the property
                    ' sharing of the folder containg the file.  
                    ' FileWebRequest.Credentials property cannot be used for this purpose.
                    readStream.Write(byteArray, 0, userInput.Length)


                    Console.WriteLine(ControlChars.Lf + "The String you entered was successfully written to the file.")

                    readStream.Close()

                Catch e As WebException
                    Console.WriteLine(("WebException is: " + e.Message))
                Catch e As UriFormatException
                    Console.WriteLine(("UriFormatWebException is: " + e.Message))
                End Try

            End Sub

            Public Shared Sub Main(ByVal args() As String)

                If args.Length < 2 Then
                    showUsage()
                Else
                    makeFileRequest(args(0), Integer.Parse(args(1)))
                    writeToFile()
                End If

            End Sub

        End Class



    End Module

End Namespace

備註

類別 FileWebRequest 會 WebRequestabstract 實作統一資源識別項 (URI 的基類，) 使用該 file:// 配置來要求本機檔案。

請勿使用 建 FileWebRequest 構函式。 WebRequest.Create使用 方法來初始化 類別的新實例 FileWebRequest 。 如果 URI 配置為 file:// ，則 Create 方法會傳 FileWebRequest 回 物件。

方法 GetResponse 會針對 屬性中指定的 RequestUri 檔案提出同步要求，並傳回 FileWebResponse 包含回應的 物件。 您可以使用 和 EndGetResponse 方法來對檔案 BeginGetResponse 提出非同步要求。

當您想要將資料寫入檔案時， GetRequestStream 方法會 Stream 傳回要寫入的實例。 BeginGetRequestStream和 EndGetRequestStream 方法會提供寫入資料流程的非同步存取。

類別 FileWebRequest 依賴 File 類別來處理錯誤和程式碼存取安全性。

建構函式

FileWebRequest(SerializationInfo, StreamingContext)
已淘汰.
已淘汰.
已淘汰.

初始化 FileWebRequest 類別的新執行個體，這個執行個體是來自 SerializationInfo 和 StreamingContext 類別的指定執行個體。

屬性

AuthenticationLevel

取得或設定值，指出用於這個要求的驗證和模擬等級。

(繼承來源 WebRequest)
CachePolicy

取得或設定這個要求的快取原則。

(繼承來源 WebRequest)
ConnectionGroupName

取得或設定要求的連線群組名稱。 這個屬性保留給未來的版本使用。
ContentLength

取得或設定正在傳送之資料的內容長度。
ContentType

取得或設定正在傳送之資料的內容類型。 這個屬性保留給未來的版本使用。
CreatorInstance
已淘汰.

在子代類別中覆寫時，取得衍生自 IWebRequestCreate 類別的 Factory 物件，用來建立執行個體化的 WebRequest 以對指定的 URI 提出要求。

(繼承來源 WebRequest)
Credentials

取得或設定與這個要求關聯的認證。 這個屬性保留給未來的版本使用。
Headers

取得與要求關聯的名稱/值組的集合。 這個屬性保留給未來的版本使用。
ImpersonationLevel

取得或設定目前要求的模擬等級。

(繼承來源 WebRequest)
Method

取得或設定要求所使用的通訊協定 (Protocol) 方法。 這個屬性保留給未來的版本使用。
PreAuthenticate

取得或設定值，指示是否要預先驗證要求。 這個屬性保留給未來的版本使用。
Proxy

取得或設定這個要求所使用的網路 Proxy。 這個屬性保留給未來的版本使用。
RequestUri

取得要求的統一資源識別元 (URI)。
Timeout

取得或設定要求逾時之前的時間長度。
UseDefaultCredentials

永遠擲回 NotSupportedException。
UseDefaultCredentials

在子代類別中覆寫時，取得或設定 Boolean 值，控制 DefaultCredentials 是否隨著要求傳送。

(繼承來源 WebRequest)

方法

Abort()

取消對網際網路資源的要求。
Abort()

中止要求。

(繼承來源 WebRequest)
BeginGetRequestStream(AsyncCallback, Object)

開始用以寫入資料之 Stream 物件的非同步要求。
BeginGetResponse(AsyncCallback, Object)

開始檔案系統資源的非同步要求。
CreateObjRef(Type)

建立包含所有相關資訊的物件，這些資訊是產生用來與遠端物件通訊的所需 Proxy。

(繼承來源 MarshalByRefObject)
EndGetRequestStream(IAsyncResult)

結束應用程式用來寫入資料之 Stream 執行個體的非同步要求。
EndGetResponse(IAsyncResult)

結束檔案系統資源的非同步要求。
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)
GetLifetimeService()
已淘汰.

擷取控制這個執行個體存留期 (Lifetime) 原則的目前存留期服務物件。

(繼承來源 MarshalByRefObject)
GetObjectData(SerializationInfo, StreamingContext)
已淘汰.

將序列化目標物件所需的資料填入 SerializationInfo。
GetObjectData(SerializationInfo, StreamingContext)
已淘汰.

將序列化目標物件所需的資料填入 SerializationInfo。

(繼承來源 WebRequest)
GetRequestStream()

傳回 Stream 物件，用於將資料寫入至檔案系統資源。
GetRequestStreamAsync()

以非同步作業的方式傳回資料流，將資料寫入檔案系統資源。
GetRequestStreamAsync()

在子代類別中覆寫時，傳回以非同步作業方式將資料寫入網際網路資源的 Stream。

(繼承來源 WebRequest)
GetResponse()

傳回對檔案系統要求的回應。
GetResponseAsync()

以非同步作業方式傳回檔案系統要求的回應。
GetResponseAsync()

在子代類別中覆寫時，傳回對網際網路要求的回應，做為非同步作業。

(繼承來源 WebRequest)
GetType()

取得目前執行個體的 Type。

(繼承來源 Object)
InitializeLifetimeService()
已淘汰.

取得存留期服務物件，以控制這個執行個體的存留期原則。

(繼承來源 MarshalByRefObject)
MemberwiseClone()

建立目前 Object 的淺層複製。

(繼承來源 Object)
MemberwiseClone(Boolean)

建立目前 MarshalByRefObject 物件的淺層複本。

(繼承來源 MarshalByRefObject)
ToString()

傳回代表目前物件的字串。

(繼承來源 Object)

明確介面實作

ISerializable.GetObjectData(SerializationInfo, StreamingContext)
已淘汰.

將序列化 SerializationInfo 所需的資料，填入 FileWebRequest 物件。

適用於

另請參閱