1 <?xml version="1.0" encoding="utf-8"?>

     2 <!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

     3 <!-- This component and the accompanying materials are made available under the terms of the License 

     4 "Eclipse Public License v1.0" which accompanies this distribution, 

     5 and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

     6 <!-- Initial Contributors:

     7     Nokia Corporation - initial contribution.

     8 Contributors: 

     9 -->

    10 <!DOCTYPE concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-5592E9C1-D490-538F-9B11-5EFB72DEDBE2" xml:lang="en"><title>File

    13 based dictionary store</title><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <p><codeph>CDictionaryFileStore</codeph> is a concrete implementation of a

    15 dictionary store and uses a file store in its implementation.</p>

    16 <p>Although the need for a file based dictionary store is driven by the application

    17 architecture, the following code fragments illustrate the way this store can

    18 be used.</p>

    19 <p>The code fragments shown here create and read a file based dictionary store.

    20 This dictionary store is differentiated from other dictionary stores by the

    21 UID whose value is <codeph>0x0001</codeph>.</p>

    22 <p>It should be noted that the values assigned to the UIDs are purely <i>arbitrary</i> and

    23 are used for <i>illustrative purposes only</i>.</p>

    24 <section><title>Creating the dictionary store</title> <p>This code fragment

    25 constructs an object of type <codeph>TClass</codeph> and stores it in the

    26 dictionary store, associating the stream with the UID whose value is 0x0002.</p> <p>Note

    27 that a dictionary write stream is needed to write streams to a dictionary

    28 store.</p> <codeblock id="GUID-AF74B440-E5A9-5A47-84E1-09E2243BB911" xml:space="preserve">_LIT(KFileName,"C:\\data\\stdict.dat");

    29 _LIT(KTxtData,"Text type data"):

    30 TParse dictionaryname;

    31 ...

    32 fsSession.Parse(KFileName,dictionaryname);

    33 ... 

    34            // Open the dictionary store (create if it doesn't exist)

    35 CDictionaryStore* dictstore = CDictionaryFileStore::OpenLC (fsSession, dictionaryname.FullName(),TUid::Uid(0x0001) );

    36 

    37            // Construct a TClass and put some data into it

    38 TClass thedata;

    39 thedata.iFixBuf    = KTxtData;

    40 thedata.iUintValue = 1;

    41 thedata.iIntValue  = -2; 

    42 thedata.iRealValue = 3.4;

    43 

    44            // construct the dictionary write stream and

    45            // associate the stream with the UID

    46            // whose value is 0x0002

    47 RDictionaryWriteStream out;

    48 out.AssignLC(*dictstore,TUid::Uid(0x0002));

    49 

    50            // write the TClass data to the stream

    51 out << thedata;

    52  

    53            // Commit changes to the stream

    54 out.CommitL(); 

    55 

    56            // Cleanup the dictionary stream object

    57 CleanupStack::PopAndDestroy();

    58 

    59            // Now commit all changes to the store

    60 dictstore->CommitL();

    61 

    62            // Close the dictionary store (closes the

    63            // associated file and destroys the 

    64            // dictionary store object)

    65 CleanupStack::PopAndDestroy(); </codeblock> </section>

    66 <section><title>Reopening the dictionary store</title><p>This code fragment

    67 re-opens the dictionary store and restores the

    68 <code>TClass</code> object from the stream associated with the UID whose

    69 value  is <code>0x0002</code>

    70 </p><codeph>0x0002</codeph><codeblock xml:space="preserve">_LIT(KFileName,"C:\\data\\stdict.dat");

    71 TParse dictionaryname;

    72 ...

    73 fsSession.Parse(KFileName,dictionaryname);

    74 ...

    75            // Open the dictionary store 

    76 CDictionaryStore* dictstore=CDictionaryFileStore::OpenLC(fsSession, dictionaryname.FullName(), TUid::Uid(0x0001) );

    77 

    78            // construct the dictionary read stream.

    79            // Prepare to read the stream associated with

    80            // the unique identifier whose value is 0x0002

    81 RDictionaryReadStream in;

    82 in.OpenLC(*dictstore,TUid::Uid(0x0002));

    83 

    84             // Construct a TClass object ...

    85 TClass thedata;

    86 

    87             // ... and read data from the stream

    88 in >> thedata;

    89 

    90             // Cleanup the dictionary stream object

    91             // and ...

    92             // Close the dictionary store

    93             // (closes the associated file and destroys the

    94             // dictionary store object)

    95 CleanupStack::PopAndDestroy(2);

    96 </codeblock> </section>

    97 <section><title>See also</title> <p><xref href="GUID-79F39C97-75E8-5DB1-B976-8FE76E6E60C9.dita">Dictionary

    98 stores</xref> </p> </section>

    99 </conbody></concept>