Note
Please see Azure Cognitive Services for Speech documentation for the latest supported speech solutions.
Grammar Constructor (Stream, String)
Initializes a new instance of the Grammar class from a Stream and specifies a root rule.
Namespace: Microsoft.Speech.Recognition
Assembly: Microsoft.Speech (in Microsoft.Speech.dll)
Syntax
'Declaration
Public Sub New ( _
stream As Stream, _
ruleName As String _
)
'Usage
Dim stream As Stream
Dim ruleName As String
Dim instance As New Grammar(stream, _
ruleName)
public Grammar(
Stream stream,
string ruleName
)
Parameters
- stream
Type: System.IO.Stream
A stream that describes a speech recognition grammar in a supported format.
- ruleName
Type: System.String
The identifier of the rule to use as the entry point of the speech recognition grammar, or a null reference (Nothing in Visual Basic) to use the default root rule of the grammar description.
This parameter may be a null reference (Nothing in Visual Basic).
Exceptions
| Exception | Condition |
|---|---|
| ArgumentException | ruleName cannot be resolved or is not public, or ruleName is a null reference (Nothing in Visual Basic) and the grammar description does not define a root rule. |
| ArgumentNullException | stream is a null reference (Nothing in Visual Basic). |
| FormatException | The stream does not contain a valid description or describes a grammar that contains a rule reference that cannot be resolved. |
Remarks
The stream argument:
Can never be a null reference (Nothing in Visual Basic) and must be readable.
In general, the object connected to a stream must be a grammar file that conforms to the W3C Speech Recognition Grammar Specification (SRGS) Version 1.0.
However:
If the input stream is connected to a Visual Studio Resource, the Resource can only contain grammar files in binary format with the .cfg extension.
If the input stream is connected to a DLL, that DLL must contain instances of Grammar.
The ruleName argument:
May be a null reference (Nothing in Visual Basic) or Empty.
If ruleName is not a null reference (Nothing in Visual Basic) and the rule specified is not found in the grammar being loaded, an exception is generated.
If ruleName is a null reference (Nothing in Visual Basic), and the grammar contained in the file specified does not declare a root rule, an exception is generated.
As there is no Base URI specified, any rule references must:
Use absolute URIs.
Target rules within the grammar being loaded.
Use any paths defined in the grammar object being loaded. If the stream was created from a file, this typically includes the directory where that file was located.
To create a Grammar object from a stream and specify a base URI to use to resolve relative rule references, use the Grammar(Stream, String, Uri) constructor.
Examples
The following example loads a local SRGS file (cities.xml) from a file stream and specifies a rule to use as the root of the grammar. The content of the cities.xml file appears in the XML example that follows the C# example.
// Load a cities grammar from an I/O stream, use a specific
// rule as the root of the grammar, and return the new grammar.
private static Grammar CreateGrammarFromStream2()
{
FileInfo file = new FileInfo(@"c:\temp\cities.xml");
Grammar citiesGrammar = new Grammar(file.OpenRead(), "Main");
citiesGrammar.Name = "Stream Cities Grammar 2";
return citiesGrammar;
}
<?xml version="1.0" encoding="UTF-8" ?>
<grammar version="1.0" xml:lang="en-US"
xmlns="http://www.w3.org/2001/06/grammar"
tag-format="semantics/1.0" root="Main">
<!-- cities.xml:
Defines an SRGS grammar for requesting a flight. This grammar includes
a Cities rule that lists the cities that can be used for departures
and destinations. -->
<rule id="Main">
<item>
I would like to fly from <ruleref uri="#Cities"/>
to <ruleref uri="#Cities"/>
</item>
</rule>
<rule id="Cities" scope="public">
<one-of>
<item> Seattle </item>
<item> Los Angeles </item>
<item> New York </item>
<item> Miami </item>
</one-of>
</rule>
</grammar>
See Also
Reference
Microsoft.Speech.Recognition Namespace
Microsoft.Speech.Recognition.SrgsGrammar