WebMethodAttribute.BufferResponse Property
Gets or sets whether the response for this request is buffered.
[Visual Basic] Public Property BufferResponse As Boolean [C#] public bool BufferResponse {get; set;} [C++] public: __property bool get_BufferResponse(); public: __property void set_BufferResponse(bool); [JScript] public function get BufferResponse() : Boolean; public function set BufferResponse(Boolean);
Property Value
true if the response for this request is buffered; otherwise, false. The default is true.
Remarks
Setting BufferResponse to true, serializes the response of the XML Web service method into a memory buffer until either the response is completely serialized or the buffer is full. Once the response is buffered, it is returned to the XML Web service client over the network. When BufferResponse is false, the response to the XML Web service method is sent back to the client as it is serialized. In general, you only want to set BufferResponse to false, if it is known that an XML Web service method returns large amounts of data to the client. For smaller amounts of data, XML Web service performance is better with BufferResponse to true.
When BufferResponse is false, SOAP extensions are disabled for the XML Web service method.
Example
[Visual Basic, C#] The following code example sets the BufferResponse property to false and handles the streaming of a text file back to the client. The code example demonstrates how to stream a large piece of data back to the client using a class that implements the IEnumerable interface.
[Visual Basic] <%@WebService Class="Streaming" language="VB"%> Imports System Imports System.IO Imports System.Collections Imports System.Xml.Serialization Imports System.Web.Services Imports System.Web.Services.Protocols Public Class Streaming <WebMethod(BufferResponse:=False)> _ Public Function GetTextFile(filename As String ) As TextFile Return New TextFile(filename) End Function <WebMethod> _ Public Sub CreateTextFile(contents As TextFile) contents.Close() End Sub End Class Public Class TextFile Public filename As String Private readerWriter As TextFileReaderWriter Public Sub New() End Sub Public Sub New(filename As String) Me.filename = filename End Sub <XmlArrayItem("line")> _ Public ReadOnly Property contents As TextFileReaderWriter Get readerWriter = New TextFileReaderWriter(filename) Return readerWriter End Get End Property Public Sub Close() If Not (readerWriter Is Nothing) Then readerWriter.Close() End If End Sub End Class Public Class TextFileReaderWriter Implements IEnumerable Public Filename As String Private writer As StreamWriter Public Sub New() End Sub Public Sub New(myfilename As String ) Filename = myfilename End Sub Function GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator Dim reader As StreamReader = New StreamReader(Filename) Return New TextFileEnumerator(reader) End Function Public Sub Add(line As String) If (writer Is Nothing) Then writer = New StreamWriter(Filename) End If writer.WriteLine(line) End Sub Public Sub Add(obj as Object) End Sub Public Sub Close() If Not (writer Is Nothing) Then writer.Close() End Sub End Class Public Class TextFileEnumerator Implements IEnumerator Private currentLine As String Private reader As StreamReader Public Sub New(reader As StreamReader) Me.reader = reader End Sub Public Function MoveNext() As Boolean Implements IEnumerator.MoveNext currentLine = reader.ReadLine() If (currentLine Is Nothing) Then reader.Close() Return False Else Return True End If End Function Public Sub Reset() Implements IEnumerator.Reset reader.BaseStream.Position = 0 End Sub ReadOnly Property Current As object Implements IEnumerator.Current Get Return CurrentLine End Get End Property End Class [C#] <%@WebService class="Streaming" language="C#"%> using System; using System.IO; using System.Collections; using System.Xml.Serialization; using System.Web.Services; using System.Web.Services.Protocols; public class Streaming { [WebMethod(BufferResponse=false)] public TextFile GetTextFile(string filename) { return new TextFile(filename); } [WebMethod] public void CreateTextFile(TextFile contents) { contents.Close(); } } public class TextFile { public string filename; private TextFileReaderWriter readerWriter; public TextFile() { } public TextFile(string filename) { this.filename = filename; } [XmlArrayItem("line")] public TextFileReaderWriter contents { get { readerWriter = new TextFileReaderWriter(filename); return readerWriter; } } public void Close() { if (readerWriter != null) readerWriter.Close(); } } public class TextFileReaderWriter : IEnumerable { public string Filename; private StreamWriter writer; public TextFileReaderWriter() { } public TextFileReaderWriter(string filename) { Filename = filename; } public TextFileEnumerator GetEnumerator() { StreamReader reader = new StreamReader(Filename); return new TextFileEnumerator(reader); } IEnumerator IEnumerable.GetEnumerator() { return GetEnumerator(); } public void Add(string line) { if (writer == null) writer = new StreamWriter(Filename); writer.WriteLine(line); } public void Close() { if (writer != null) writer.Close(); } } public class TextFileEnumerator : IEnumerator { private string currentLine; private StreamReader reader; public TextFileEnumerator(StreamReader reader) { this.reader = reader; } public bool MoveNext() { currentLine = reader.ReadLine(); if (currentLine == null) { reader.Close(); return false; } else return true; } public void Reset() { reader.BaseStream.Position = 0; } public string Current { get { return currentLine; } } object IEnumerator.Current { get { return Current; } } }
[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button
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Requirements
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
See Also
WebMethodAttribute Class | WebMethodAttribute Members | System.Web.Services Namespace