Grammar Constructor (Stream)

Initializes a new instance of the Grammar class from a Stream.

Namespace: Microsoft.Speech.Recognition
Assembly: Microsoft.Speech (in Microsoft.Speech.dll)

Syntax

'Declaration
Public Sub New ( _
    stream As Stream _
)
'Usage
Dim stream As Stream

Dim instance As New Grammar(stream)

public Grammar(
    Stream stream
)

Parameters

stream
Type: System.IO.Stream
A stream that describes a speech recognition grammar in a supported format.

Exceptions

Exception	Condition
ArgumentException	stream describes a grammar that does not contain a root rule.
ArgumentNullException	stream is a null reference (Nothing in Visual Basic).
FormatException	The stream does not contain a valid description of a grammar, 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 a stream is connected to must be a grammar 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 grammars files in binary format with the .cfg extension.
- If the input stream is connected to a DLL, that DLL must contain instances of Grammar.

Any object connected to stream must contain a grammar that defines a root rule. To create a Grammar object from a stream and specify a root rule, use the Grammar(Stream, String) or Grammar(Stream, String, Uri) constructor.

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 creates a speech recognition grammar from a local SRGS file (cities.xml) using a file stream. The content of the cities.xml file appears following C# example.

// Load a cities grammar from an I/O stream and
// return the new grammar. 
private static Grammar CreateGrammarFromStream()
{
  string fileName = @"c:\temp\cities.xml";
  Grammar citiesGrammar =
    new Grammar(new FileStream(fileName, FileMode.Open));
  citiesGrammar.Name = "Stream Cities Grammar";
  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>

Partilhar via

Grammar Constructor (Stream)

Syntax

Parameters

Exceptions

Remarks

Examples

See Also

Reference

Other Resources

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