Namespace:
Microsoft.Speech.Recognition
Assembly:
Microsoft.Speech (in Microsoft.Speech.dll)
Syntax
| Visual Basic (Declaration) |
|---|
Public Sub New ( _ stream As Stream, _ ruleName As String _ ) |
| Visual Basic (Usage) |
|---|
Dim stream As Stream Dim ruleName As String Dim instance As New Grammar(stream, _ ruleName) |
| C# |
|---|
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 nullNothingnullptrunita null reference (Nothing in Visual Basic) to use the default root rule of the grammar description.
This parameter may be nullNothingnullptrunita null reference (Nothing in Visual Basic).
Exceptions
| Exception | Condition |
|---|---|
| ArgumentException | Thrown when stream or ruleName have invalid values. Thrown when the stream is connected to a grammar that does not contain the rule ruleName, or requires initialization parameters, or has a relative rule reference not resolvable by the default base System.Uri rule for grammars. |
Remarks
The stream argument:
Can never be nullNothingnullptrunita 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 nullNothingnullptrunita null reference (Nothing in Visual Basic) or Empty.
If ruleName is not nullNothingnullptrunita 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 nullNothingnullptrunita 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.
| C# | Copy Code |
|---|---|
// 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 | Copy Code |
|---|---|
<?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
