Metodo DirectiveProcessor.ProcessDirective
Quando è sottoposto a override in una classe derivata, elabora una singola direttiva da un file modello.
Spazio dei nomi: Microsoft.VisualStudio.TextTemplating
Assembly: Microsoft.VisualStudio.TextTemplating.10.0 (in Microsoft.VisualStudio.TextTemplating.10.0.dll)
Sintassi
'Dichiarazione
Public MustOverride Sub ProcessDirective ( _
directiveName As String, _
arguments As IDictionary(Of String, String) _
)
public abstract void ProcessDirective(
string directiveName,
IDictionary<string, string> arguments
)
public:
virtual void ProcessDirective(
String^ directiveName,
IDictionary<String^, String^>^ arguments
) abstract
abstract ProcessDirective :
directiveName:string *
arguments:IDictionary<string, string> -> unit
public abstract function ProcessDirective(
directiveName : String,
arguments : IDictionary<String, String>
)
Parametri
- directiveName
Tipo: System.String
Nome della direttiva da elaborare.
- arguments
Tipo: System.Collections.Generic.IDictionary<String, String>
Argomenti per la direttiva.
Note
Un processore di direttiva può supportare molte direttive diverse. Quando viene chiamato il metodo ProcessDirective, le istruzioni condizionali vengono eseguite solo con la direttiva specifica chiamata.
Le direttive consentono di elaborare gli argomenti e di generare codice da aggiungere alla classe Transformation generata.
Esempi
Nell'esempio di codice seguente viene illustrata una possibile implementazione di un processore di direttiva personalizzato. Questo esempio di codice fa parte di un esempio più completo fornito per la classe DirectiveProcessor.
public override void ProcessDirective(string directiveName, IDictionary<string, string> arguments)
{
if (string.Compare(directiveName, "CoolDirective", StringComparison.OrdinalIgnoreCase) == 0)
{
string fileName;
if (!arguments.TryGetValue("FileName", out fileName))
{
throw new DirectiveProcessorException("Required argument 'FileName' not specified.");
}
if (string.IsNullOrEmpty(fileName))
{
throw new DirectiveProcessorException("Argument 'FileName' is null or empty.");
}
//Now we add code to the generated transformation class.
//This directive supports either Visual Basic or C#, so we must use the
//System.CodeDom to create the code.
//If a directive supports only one language, you can hard code the code.
//--------------------------------------------------------------------------
CodeMemberField documentField = new CodeMemberField();
documentField.Name = "document" + directiveCount + "Value";
documentField.Type = new CodeTypeReference(typeof(XmlDocument));
documentField.Attributes = MemberAttributes.Private;
CodeMemberProperty documentProperty = new CodeMemberProperty();
documentProperty.Name = "Document" + directiveCount;
documentProperty.Type = new CodeTypeReference(typeof(XmlDocument));
documentProperty.Attributes = MemberAttributes.Public;
documentProperty.HasSet = false;
documentProperty.HasGet = true;
CodeExpression fieldName = new CodeFieldReferenceExpression(new CodeThisReferenceExpression(), documentField.Name);
CodeExpression booleanTest = new CodeBinaryOperatorExpression(fieldName, CodeBinaryOperatorType.IdentityEquality, new CodePrimitiveExpression(null));
CodeExpression rightSide = new CodeMethodInvokeExpression(new CodeTypeReferenceExpression("XmlReaderHelper"), "ReadXml", new CodePrimitiveExpression(fileName));
CodeStatement[] thenSteps = new CodeStatement[] { new CodeAssignStatement(fieldName, rightSide) };
CodeConditionStatement ifThen = new CodeConditionStatement(booleanTest, thenSteps);
documentProperty.GetStatements.Add(ifThen);
CodeStatement s = new CodeMethodReturnStatement(fieldName);
documentProperty.GetStatements.Add(s);
CodeGeneratorOptions options = new CodeGeneratorOptions();
options.BlankLinesBetweenMembers = true;
options.IndentString = " ";
options.VerbatimOrder = true;
options.BracingStyle = "C";
using (StringWriter writer = new StringWriter(codeBuffer, CultureInfo.InvariantCulture))
{
codeDomProvider.GenerateCodeFromMember(documentField, writer, options);
codeDomProvider.GenerateCodeFromMember(documentProperty, writer, options);
}
}//end CoolDirective
//One directive processor can contain many directives.
//If you want to support more directives, the code goes here...
//-----------------------------------------------------------------
if (string.Compare(directiveName, "supercooldirective", StringComparison.OrdinalIgnoreCase) == 0)
{
//code for SuperCoolDirective goes here...
}//end SuperCoolDirective
//Track how many times the processor has been called.
//-----------------------------------------------------------------
directiveCount++;
}//end ProcessDirective
Public Overrides Sub ProcessDirective(ByVal directiveName As String, ByVal arguments As IDictionary(Of String, String))
If String.Compare(directiveName, "CoolDirective", StringComparison.OrdinalIgnoreCase) = 0 Then
Dim fileName As String
If Not (arguments.TryGetValue("FileName", fileName)) Then
Throw New DirectiveProcessorException("Required argument 'FileName' not specified.")
End If
If String.IsNullOrEmpty(fileName) Then
Throw New DirectiveProcessorException("Argument 'FileName' is null or empty.")
End If
'Now we add code to the generated transformation class.
'This directive supports either Visual Basic or C#, so we must use the
'System.CodeDom to create the code.
'If a directive supports only one language, you can hard code the code.
'--------------------------------------------------------------------------
Dim documentField As CodeMemberField = New CodeMemberField()
documentField.Name = "document" & directiveCount & "Value"
documentField.Type = New CodeTypeReference(GetType(XmlDocument))
documentField.Attributes = MemberAttributes.Private
Dim documentProperty As CodeMemberProperty = New CodeMemberProperty()
documentProperty.Name = "Document" & directiveCount
documentProperty.Type = New CodeTypeReference(GetType(XmlDocument))
documentProperty.Attributes = MemberAttributes.Public
documentProperty.HasSet = False
documentProperty.HasGet = True
Dim fieldName As CodeExpression = New CodeFieldReferenceExpression(New CodeThisReferenceExpression(), documentField.Name)
Dim booleanTest As CodeExpression = New CodeBinaryOperatorExpression(fieldName, CodeBinaryOperatorType.IdentityEquality, New CodePrimitiveExpression(Nothing))
Dim rightSide As CodeExpression = New CodeMethodInvokeExpression(New CodeTypeReferenceExpression("XmlReaderHelper"), "ReadXml", New CodePrimitiveExpression(fileName))
Dim thenSteps As CodeStatement() = New CodeStatement() {New CodeAssignStatement(fieldName, rightSide)}
Dim ifThen As CodeConditionStatement = New CodeConditionStatement(booleanTest, thenSteps)
documentProperty.GetStatements.Add(ifThen)
Dim s As CodeStatement = New CodeMethodReturnStatement(fieldName)
documentProperty.GetStatements.Add(s)
Dim options As CodeGeneratorOptions = New CodeGeneratorOptions()
options.BlankLinesBetweenMembers = True
options.IndentString = " "
options.VerbatimOrder = True
options.BracingStyle = "VB"
Using writer As StringWriter = New StringWriter(codeBuffer, CultureInfo.InvariantCulture)
codeDomProvider.GenerateCodeFromMember(documentField, writer, options)
codeDomProvider.GenerateCodeFromMember(documentProperty, writer, options)
End Using
End If 'CoolDirective
'One directive processor can contain many directives.
'If you want to support more directives, the code goes here...
'-----------------------------------------------------------------
If String.Compare(directiveName, "supercooldirective", StringComparison.OrdinalIgnoreCase) = 0 Then
'code for SuperCoolDirective goes here
End If 'SuperCoolDirective
'Track how many times the processor has been called.
'-----------------------------------------------------------------
directiveCount += 1
End Sub 'ProcessDirective
Sicurezza di .NET Framework
- Attendibilità totale per il chiamante immediato. Impossibile utilizzare questo membro in codice parzialmente attendibile. Per ulteriori informazioni, vedere Utilizzo di librerie da codice parzialmente attendibile.
Vedere anche
Riferimenti
Spazio dei nomi Microsoft.VisualStudio.TextTemplating