MessageQuery Třída
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Definuje základní chování tříd, které se používají k hledání konkrétních korelací dat ve zprávě.
public ref class MessageQuery abstractpublic abstract class MessageQuerytype MessageQuery = classPublic MustInherit Class MessageQuery- Dědičnost
-
MessageQuery
- Odvozené
Příklady
Následující příklad vytvoří zprávu a dotazy na zprávy XPath. Dotazy se vyhodnocují XPathMessageQuery objekty obsažené v objektu XPathMessageQueryCollection. Výsledky každého dotazu se testují pomocí vlastnosti ResultType třídy XPathResult.
using System;
using System.IO;
using System.Xml;
using System.ServiceModel.Dispatcher;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Xml.XPath;
namespace MessageQueryExamples
{
class Program
{
static void Main(string[] args)
{
// The XPathMessageQueryCollection inherits from MessageQueryCollection.
XPathMessageQueryCollection queryCollection = MessageHelper.SetupQueryCollection();
// Create a message and a copy of the message. You must create a buffered copy to access the message body.
Message mess = MessageHelper.CreateMessage();
MessageBuffer mb = mess.CreateBufferedCopy(int.MaxValue);
// Evaluate every query in the collection.
foreach (XPathMessageQuery q in queryCollection)
{
// Evaluate the query. Note the result type is an XPathResult.
XPathResult qPathResult = q.Evaluate<XPathResult>(mb);
// Use the XPathResult to determine the result type.
Console.WriteLine("Result type: {0}", qPathResult.ResultType);
// The following code prints the result according to the result type.
if (qPathResult.ResultType == XPathResultType.String)
Console.WriteLine("{0} = {1}", q.Expression, qPathResult.GetResultAsString());
if (qPathResult.ResultType == XPathResultType.NodeSet)
{
// Iterate through the node set.
XPathNodeIterator ns = qPathResult.GetResultAsNodeset();
foreach (XPathNavigator n in ns)
Console.WriteLine("\t{0} = {1}", q.Expression, n.Value);
}
if (qPathResult.ResultType == XPathResultType.Number)
Console.WriteLine("\t{0} = {1}", q.Expression, qPathResult.GetResultAsNumber());
if (qPathResult.ResultType == XPathResultType.Boolean)
Console.WriteLine("\t{0} ={1}", q.Expression, qPathResult.GetResultAsBoolean());
if (qPathResult.ResultType == XPathResultType.Error)
Console.WriteLine("\tError!");
}
Console.WriteLine();
// The alternate code below demonstrates similar funcionality using a MessageQueryTable.
// The difference is the KeyValuePair that requires a key to index each value.
// The code uses the expression as the key, and an arbitrary value for the value.
//MessageQueryTable<string> mq = MessageHelper.SetupTable();
//foreach (KeyValuePair<MessageQuery, string> kv in mq)
//{
// XPathMessageQuery xp = (XPathMessageQuery)kv.Key;
// Console.WriteLine("Value = {0}", kv.Value);
// Console.WriteLine("{0} = {1}", xp.Expression, xp.Evaluate<string>(mb));
//}
Console.ReadLine();
}
}
public class MessageHelper
{
static string messageBody =
"<PurchaseOrder date='today'>" +
"<Number>ABC-2009-XYZ</Number>" +
"<Department>OnlineSales</Department>" +
"<Items>" +
"<Item product='nail' quantity='1'>item1</Item>" +
"<Item product='screw' quantity='2'>item2</Item>" +
"<Item product='brad' quantity='3'>" +
"<SpecialOffer/>" +
"Special item4" +
"</Item>" +
"<Item product='SpecialNails' quantity='9'>item5</Item>" +
"<Item product='SpecialBrads' quantity='11'>" +
"<SpecialOffer/>" +
"Special item6" +
"</Item>" +
"<Item product='hammer' quantity='1'>item7</Item>" +
"<Item product='wrench' quantity='2'>item8</Item>" +
"</Items>" +
"<Comments>" +
"Rush order" +
"</Comments>" +
"</PurchaseOrder>";
public static string xpath = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@quantity = 1]";
public static string xpath2 = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@product = 'nail']";
public static string xpath3 = "/s12:Envelope/s12:Body/PurchaseOrder/Comments";
public static string xpath4 = "count(/s12:Envelope/s12:Body/PurchaseOrder/Items/Item)";
public static string xpath5 = "substring(string(/s12:Envelope/s12:Body/PurchaseOrder/Number),5,4)";
public static string xpath6 = "/s12:Envelope/s12:Body/PurchaseOrder/Department='OnlineSales'";
public static string xpath7 = "//PurchaseOrder/@date";
public static string xpath8 = "//SpecialOffer/ancestor::Item[@product = 'brad']";
// Invoke the correlation data function.
public static string xpath9 = "sm:correlation-data('CorrelationData1')";
public static string xpath10 = "sm:correlation-data('CorrelationData2')";
public static string xpath11 = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@quantity = 2]";
public static Message CreateMessage()
{
StringReader stringReader = new StringReader(messageBody);
XmlTextReader xmlReader = new XmlTextReader(stringReader);
Message message = Message.CreateMessage(MessageVersion.Soap12WSAddressing10, "http://purchaseorder", xmlReader);
// Add two correlation properties using lambda expressions. The property names are
// CorrelationData1 and CorrelationData2. The first goes to "value1" and the
// second to "value2". You can use your own property names and values.
CorrelationDataMessageProperty data = new CorrelationDataMessageProperty();
data.Add("CorrelationData1", () => "value1");
data.Add("CorrelationData2", () => "value2");
message.Properties[CorrelationDataMessageProperty.Name] = data;
return message;
}
public static XPathMessageQueryCollection SetupQueryCollection()
{
// Create the query collection and add the XPath queries to it. To create
// the query, you must also use a new XPathMessageContext.
XPathMessageQueryCollection queryCollection = new XPathMessageQueryCollection();
XPathMessageContext context = new XPathMessageContext();
queryCollection.Add(new XPathMessageQuery(xpath, context));
queryCollection.Add(new XPathMessageQuery(xpath2, context));
queryCollection.Add(new XPathMessageQuery(xpath3, context));
queryCollection.Add(new XPathMessageQuery(xpath4, context));
queryCollection.Add(new XPathMessageQuery(xpath5, context));
queryCollection.Add(new XPathMessageQuery(xpath6, context));
queryCollection.Add(new XPathMessageQuery(xpath7, context));
queryCollection.Add(new XPathMessageQuery(xpath8, context));
queryCollection.Add(new XPathMessageQuery(xpath9, context));
queryCollection.Add(new XPathMessageQuery(xpath10, context));
queryCollection.Add(new XPathMessageQuery(xpath11, context));
return queryCollection;
}
public static MessageQueryTable<string> SetupTable()
{
// This is optional code to demonstrate using a MessageQueryTable.
// Compare this to the MessageQueryCollection.
MessageQueryTable<string> table = new MessageQueryTable<string>();
XPathMessageContext context = new XPathMessageContext();
// The code adds a KeyValuePair to the table. Each pair requires
// a query used as the Key, and a value that is paired to the key.
table.Add(new XPathMessageQuery(xpath, context), "value10");
table.Add(new XPathMessageQuery(xpath2, context), "value20");
table.Add(new XPathMessageQuery(xpath3, context), "value30");
table.Add(new XPathMessageQuery(xpath4, context), "value40");
table.Add(new XPathMessageQuery(xpath5, context), "value50");
table.Add(new XPathMessageQuery(xpath6, context), "value60");
table.Add(new XPathMessageQuery(xpath7, context), "value70");
table.Add(new XPathMessageQuery(xpath8, context), "value80");
table.Add(new XPathMessageQuery(xpath9, context), "value90");
table.Add(new XPathMessageQuery(xpath10, context), "value100");
table.Add(new XPathMessageQuery(xpath11, context), "value110");
return table;
}
}
}
Imports System.IO
Imports System.Xml
Imports System.ServiceModel.Dispatcher
Imports System.ServiceModel
Imports System.ServiceModel.Channels
Imports System.Xml.XPath
Namespace MessageQueryExamples
Public Class Program
Public Shared Sub Main(ByVal args As String())
' The XPathMessageQueryCollection inherits from MessageQueryCollection.
Dim queryCollection As XPathMessageQueryCollection = MessageHelper.SetupQueryCollection()
' Create a message and a copy of the message. You must create a buffered copy to access the message body.
Dim mess As Message = MessageHelper.CreateMessage()
Dim mb As MessageBuffer = mess.CreateBufferedCopy(Integer.MaxValue)
' Evaluate every query in the collection.
Dim q As XPathMessageQuery
For Each q In queryCollection
' Evaluate the query. Note the result type is an XPathResult.
Dim qPathResult As XPathResult = q.Evaluate(Of XPathResult)(mb)
' Use the XPathResult to determine the result type.
Console.WriteLine("Result type: {0}", qPathResult.ResultType)
' The following code prints the result according to the result type.
If qPathResult.ResultType = XPathResultType.String Then
Console.WriteLine("{0} = {1}", q.Expression, qPathResult.GetResultAsString())
End If
If (qPathResult.ResultType = XPathResultType.NodeSet) Then
' Iterate through the node set.
Dim ns As XPathNodeIterator = qPathResult.GetResultAsNodeset()
Dim n As XPathNavigator
For Each n In ns
Console.WriteLine(" {0} = {1}", q.Expression, n.Value)
Next
End If
If qPathResult.ResultType = XPathResultType.Number Then
Console.WriteLine(" {0} = {1}", q.Expression, qPathResult.GetResultAsNumber())
End If
If qPathResult.ResultType = XPathResultType.Boolean Then
Console.WriteLine(" {0} ={1}", q.Expression, qPathResult.GetResultAsBoolean())
End If
If qPathResult.ResultType = XPathResultType.Error Then
Console.WriteLine(" Error!")
End If
Next
Console.WriteLine()
' The alternate code below demonstrates similar funcionality using a MessageQueryTable.
' The difference is the KeyValuePair that requires a key to index each value.
' The code uses the expression as the key, and an arbitrary value for the value.
'Dim mq As MessageQueryTable(Of String) = MessageHelper.SetupTable()
'Dim kv As KeyValuePair(Of MessageQuery, String)
'For Each kv In mq
' '
' Dim xp As XPathMessageQuery = CType(kv.Key, XPathMessageQuery)
' Console.WriteLine("Value = {0}", kv.Value)
' Console.WriteLine("{0} = {1}", xp.Expression, xp.Evaluate(Of String)(mb))
'Next
Console.ReadLine()
End Sub
Private Shared Sub Evaluate(ByVal p1 As Object)
Throw New NotImplementedException
End Sub
End Class
Public Class MessageHelper
Shared messageBody As String = _
"<PurchaseOrder date='today'>" + _
"<Number>ABC-2009-XYZ</Number>" + _
"<Department>OnlineSales</Department>" + _
"<Items>" + _
"<Item product='nail' quantity='1'>item1</Item>" + _
"<Item product='screw' quantity='2'>item2</Item>" + _
"<Item product='brad' quantity='3'>" + _
"<SpecialOffer/>" + _
"Special item4" + _
"</Item>" + _
"<Item product='SpecialNails' quantity='9'>item5</Item>" + _
"<Item product='SpecialBrads' quantity='11'>" + _
"<SpecialOffer/>" + _
"Special item6" + _
"</Item>" + _
"<Item product='hammer' quantity='1'>item7</Item>" + _
"<Item product='wrench' quantity='2'>item8</Item>" + _
"</Items>" + _
"<Comments>" + _
"Rush order" + _
"</Comments>" + _
"</PurchaseOrder>"
Public Shared xpath As String = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@quantity = 1]"
Public Shared xpath2 As String = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@product = 'nail']"
Public Shared xpath3 As String = "/s12:Envelope/s12:Body/PurchaseOrder/Comments"
Public Shared xpath4 As String = "count(/s12:Envelope/s12:Body/PurchaseOrder/Items/Item)"
Public Shared xpath5 As String = "substring(string(/s12:Envelope/s12:Body/PurchaseOrder/Number),5,4)"
Public Shared xpath6 As String = "/s12:Envelope/s12:Body/PurchaseOrder/Department='OnlineSales'"
Public Shared xpath7 As String = "//PurchaseOrder/@date"
Public Shared xpath8 As String = "//SpecialOffer/ancestor::Item[@product = 'brad']"
' Invoke the correlation data function.
Public Shared xpath9 As String = "sm:correlation-data('CorrelationData1')"
Public Shared xpath10 As String = "sm:correlation-data('CorrelationData2')"
Public Shared xpath11 As String = "/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@quantity = 2]"
Public Shared Function CreateMessage() As Message
Dim stringReader As New StringReader(messageBody)
Dim xmlReader As New XmlTextReader(stringReader)
Dim message As Message = message.CreateMessage( _
MessageVersion.Soap12WSAddressing10, "http://purchaseorder", xmlReader)
' Add two correlation properties using lambda expressions. The property names are
' CorrelationData1 and CorrelationData2. The first goes to "value1" and the
' second to "value2". You can use your own property names and values.
Dim data As New CorrelationDataMessageProperty()
data.Add("CorrelationData1", Function() "value1")
data.Add("CorrelationData2", Function() "value2")
message.Properties(CorrelationDataMessageProperty.Name) = data
Return message
End Function
Public Shared Function SetupQueryCollection() As XPathMessageQueryCollection
' Create the query collection and add the XPath queries to it. To create
' the query, you must also use a new XPathMessageContext.
Dim queryCollection As New XPathMessageQueryCollection()
Dim context As XPathMessageContext = New XPathMessageContext()
queryCollection.Add(New XPathMessageQuery(xpath, context))
queryCollection.Add(New XPathMessageQuery(xpath2, context))
queryCollection.Add(New XPathMessageQuery(xpath3, context))
queryCollection.Add(New XPathMessageQuery(xpath4, context))
queryCollection.Add(New XPathMessageQuery(xpath5, context))
queryCollection.Add(New XPathMessageQuery(xpath6, context))
queryCollection.Add(New XPathMessageQuery(xpath7, context))
queryCollection.Add(New XPathMessageQuery(xpath8, context))
queryCollection.Add(New XPathMessageQuery(xpath9, context))
queryCollection.Add(New XPathMessageQuery(xpath10, context))
queryCollection.Add(New XPathMessageQuery(xpath11, context))
Return queryCollection
End Function
Public Shared Function SetupTable() As MessageQueryTable(Of String)
' This is optional code to demonstrate using a MessageQueryTable.
' Compare this to the MessageQueryCollection.
Dim table As MessageQueryTable(Of String) = New MessageQueryTable(Of String)()
Dim context As XPathMessageContext = New XPathMessageContext()
' The code adds a KeyValuePair to the table. Each pair requires
' a query used as the Key, and a value that is paired to the key.
table.Add(New XPathMessageQuery(xpath, context), "value10")
table.Add(New XPathMessageQuery(xpath2, context), "value20")
table.Add(New XPathMessageQuery(xpath3, context), "value30")
table.Add(New XPathMessageQuery(xpath4, context), "value40")
table.Add(New XPathMessageQuery(xpath5, context), "value50")
table.Add(New XPathMessageQuery(xpath6, context), "value60")
table.Add(New XPathMessageQuery(xpath7, context), "value70")
table.Add(New XPathMessageQuery(xpath8, context), "value80")
table.Add(New XPathMessageQuery(xpath9, context), "value90")
table.Add(New XPathMessageQuery(xpath10, context), "value100")
table.Add(New XPathMessageQuery(xpath11, context), "value110")
Return table
End Function
End Class
End Namespace
Poznámky
Třída MessageQuery je podobná MessageFilter třídě. Místo vrácení shod Evaluate však metoda vrátí výsledky vyhodnocení dotazu na zprávu. Výsledkem dotazu je hodnota ve zprávě. Hodnotu použijte jako klíč ke korelaci zprávy s jinými zprávami. Chcete-li přidat novou vlastnost pro data, použijte Add metodu CorrelationDataMessageProperty třídy.
Poznámka:
Konkrétní implementaci MessageQuery, viz XPathMessageQuery třída.
Použití tříd XPathMessageQuery a MessageQueryCollection
Proces dotazu můžete optimalizovat tak, že vytvoříte sadu objektů dotazu a vložíte je do instance MessageQueryCollection třídy.
Poznámka:
Konkrétní implementaci MessageQueryCollection, viz XPathMessageQueryCollection třída.
Běžným použitím je naplnění kolekce dotazy, které mají stejný predikát XPath, ale liší se pouze v konečné hodnotě listu. Například následující dotazy XPath jsou s výjimkou konečné klauzule stejné. První dotazy pro všechny prvky, které mají atribut množství nastavený na hodnotu 1, a druhý dotaz na prvky s atributem produktu nastaveným na "Contoso"):
"/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@quantity = 1]"
"/s12:Envelope/s12:Body/PurchaseOrder/Items/Item[@product = 'Contoso']"
Třída MessageQueryCollection umožňuje vytvářet tabulky dotazů, které se liší pouze mírně, což umožňuje efektivnější zpracování.
Případně můžete pomocí MessageQueryTable<TItem> třídy ukládat a vyhodnocovat dotazy na zprávy.
Konstruktory
| Name | Description |
|---|---|
| MessageQuery() |
Inicializuje novou instanci MessageQuery třídy. |
Metody
| Name | Description |
|---|---|
| CreateMessageQueryCollection() |
Vytvoří kolekci dotazů, které vrátí konkrétní typ dat přidružených k nim. |
| Equals(Object) |
Určuje, zda je zadaný objekt roven aktuálnímu objektu. (Zděděno od Object) |
| Evaluate<TResult>(Message) |
Při přepsání v odvozené třídě spustí dotaz na zprávu a vrátí výsledek. Tělo nelze dotazovat. |
| Evaluate<TResult>(MessageBuffer) |
Při přepsání v odvozené třídě spustí dotaz na zprávu a vrátí výsledek. |
| GetHashCode() |
Slouží jako výchozí funkce hash. (Zděděno od Object) |
| GetType() |
Získá Type aktuální instance. (Zděděno od Object) |
| MemberwiseClone() |
Vytvoří mělkou kopii aktuálního Object. (Zděděno od Object) |
| ToString() |
Vrátí řetězec, který představuje aktuální objekt. (Zděděno od Object) |
