grouping of repetitive functions on User Archives in one function.

Sample program: grouping of repetitive functions on User Archives in one function.QUESTION:How can I reduce the C code with scripts for accessing User Archive? ANSWER:If you program scripts for accessing User Archive, then there are large volumes of code for the administration tasks. This code is the same for accessing all User Archives. The example here shows an option for grouping the administration tasks together in one function. The script structure looks like this for standard programming methods: 1. Generating the sorting and filtering conditions 2. Setting up a connection to the User ArchiveuaConnectuaQueryArchiveByNameif error: return 3. Setting the sorting and filtering conditionsuaArchiveSetFilteruaArchiveSetSort 4. Opening the queryuaArchiveOpen 5. Actually working with the queryRead, write, delete, insert and so on. 6. Clearing down the connection to the User ArchiveuaArchiveCloseuaReleaseArchiveuaDisconnect If you program everything with fault check in one function, the function becomes too large and unclear.If you take a close look at the list above, you will be able to see that only points 1 and 5 change from case to case.All the other points remain the same no matter what structure the User Archive has. You can split the above structure into 3 functions. 1. The task-related function takes care of point 1. It generates the filters and sorting conditions. 2. A general function that encapsulates all administration actions. This function applies for ALL User Archives. The function receive a callback function as parameter. This callback function is called either for each entry in the query or just once for the entire archive. 3. A callback function, this function process point 5. This division means that you dont have to worry about the administration actions. You program just one function for query generation and one archive-related function, which processes the archive entries. In the following example we use the function uaUtilityEnumRecords. Function description: BOOL uaUtilityEnumRecords( Const char* pszArchiveName ,const char* lpszFilter,const char* lpszSort,BOOL ( UserFunc )( UAHARCHIVE* phUA, void* pUserData ),void* pUserData ) Parameters: pszArchiveName: Pointer to a zero-terminated string. The string contains the name of the archive as it appears in the User Archive editor. lpszFilter: Pointer to a zero-terminated string. The string contains the filter condition for the archive. The pointer can also be ZERO. lpszSort: Pointer to a zero-terminated string. The string contains the sorting condition for the archive. The pointer can also be ZERO. UserFunc: Name of a callback function. The function is called for each entry if you transfer a filter. The function is called once for the entire archive if you do not transfer a filter. The function must be of the following type:BOOL ( UserFunc )( UAHARCHIVE* phUA, void* pUserData ). pUserData: Pointer to user data. The pointer is forwarded without modification to the callback function. Return value: The function returns the value TRUE if: no faults have occurred during connection setup and clear-down. the callback function always returns TRUE. Otherwise the value FALSE is returned. Function:The uaUtilityEnumRecords function carries out the following steps: 1. Sets up connection to the User Archive. 2. Sets the filter and sorting conditions if they are transferred. 3. Opens the query. 4. If no filter has been set, the function calls the callback function with the handle to the archive.If the filter exists, the callback function is called in a loop for each entry in the query with the handle to an entry. As soon as the CB function returns the value FALSE, the loop is terminated. The function uaUtilityEnumRecords then returns the FALSE. 5. After the callback function has been processed, the connection to the archive is set up. You see the code of the function in the following PDF document:uaUtilityEnumRecords_1.pdf ( 7 KB ) 代码：#include apdefap.hBOOL uaUtilityEnumRecords( const char* pszArchiveName , const char* lpszFilter, const char* lpszSort,BOOL ( UserFunc ) ( UAHARCHIVE* phUA, void* pUserData ),void* pUserData )/*Function create a Query for a User Archive specified by Filter and sort condition. Function calls for eachRecord in Query User function if Filter specified. If not filter spezified function calls user function only onetime.ParameterhArchive: Handle to a User ArchivelpszFilter: Pointer to Zerro Terminated string with Filter for User Archive. If Pointer isnt NULL functionmake new Query from Archive, and calls for EACH record User Function !If Pointer is NULL: Function create conection to User Archive whithout filter.In this Case user function is called only ONE TIME !lpszSort: pointer to zeroterminated string with sort conditionlpFunc: Pointer to User Function.pUserData: Pointer to Parameter Struct for User Function.*/BOOL returnCode = TRUE;const char* funcName = uaUtilityEnumRecords ;UAHCONNECT hConnect ;BOOL returnCode =TRUE;/ Get Connection to User ArchivesreturnCode = uaConnect( &hConnect );if( !returnCode | !hConnect )returnCode = FALSE;printf( %s fault in uaConnect rn, funcName );else/ Get Handle to Actual Archive.UAHARCHIVE hArchive;if ( ! uaQueryArchiveByName( hConnect, pszArchiveName , &hArchive ) )printf( %s: uaQueryArchive Error: %drn, funcName , uaGetLastError() );returnCode = FALSE;elseif( lpszFilter ) returnCode = uaArchiveSetFilter( hArchive, lpszFilter );if( lpszSort ) returnCode = ( returnCode & uaArchiveSetSort( hArchive , lpszSort ) );if( !returnCode )printf(%s: uaArchiveSetFilter rn, funcName );else/ Open Data returned by Queryif( uaArchiveOpen( hArchive ) )/ If Filter specified: Go to First Record in Queryif ( ! lpszFilter ) / if none Filter specified: call user funkction one Time onlyif( !( returnCode = UserFunc( &hArchive , pUserData ) ) )printf(%s error in User Funcion ! rn , funcName) ;else / Filter angegeben ( Filter specified )BOOL isRecord = uaArchiveMoveFirst ( hArchive ) ;/ If Filter specified: For each Record in Query : iterate all Records and Call User Functionwhile( isRecord & lpszFilter )if( !( returnCode = UserFunc( &hArchive , pUserData ) ) )printf(%s error in User Funcion ! rn , funcName) ;isRecord = uaArchiveMoveNext( hArchive ); /. while. / if !Filterif ( !uaArchiveClose ( hArchive )printf(%s error in uaArchiveClose ! rn , funcName) ;returnCode = FALSE ;/ uaArchiveOpen / . SetFilterif( !uaReleaseArchive ( hArchive ) )printf(%s error in uaReleaseArchive! rn , funcName) ;returnCode = FALSE ; / uaQueryArchiveByNameif( !uaDisconnect( hConnect ) )printf(%s error in uaDisconnect ! rn , funcName) ;returnCode = FALSE ; / . if( !returnCode | !hConnect )return returnCode;Interface of the callback functions: phUA: Pointer to a User Archive handle. The handle can refer to the entire archive or just one single entry. pUserData: Pointer to the user data. Return value:In the case of faults, functions should return the value FALSE. Sample project: The sample project demonstrates the application of the function uaUtilityEnumRecords. The sample project was created with WinCC V5.0. You can also use the function with WinCC V 4.02. The sample project contains sample User Archive called JobData. The archive has two columns. One column for the product designation and the other column for the product quantity. In the start image there are four buttons that access the archive. The Insert Job button inserts a new line in the archive.InsertButton_1.pdf ( 3 KB ) Button Insert Job#include apdefap.hvoid OnClick(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)if( uaUtilityEnumRecords( JobData , NULL , NULL , InsertJobCB , NULL ) )printf( Insert O.K. rn );else printf( Insert failed ! rn );Function InsertJobCB#include apdefap.hBOOL InsertJobCB( UAHARCHIVE* phArchive , void* pUserData )BOOL rc = TRUE; / Return codechar* szProductName = GetTagCharWait( ProductName ); / read name of productlong lPartsToProd = ( long ) GetTagWord( BlanksToProduce ); / read number of partsif( ! uaArchiveSetFieldValueString( *phArchive, 1 , szProductName ) | / write productname to archive! uaArchiveSetFieldValueLong( *phArchive, 2 , lPartsToProd ) ) / write number of parts to archiveprintf( InsertJobCB: error on writing to record rn );rc = FALSE ;elseif( !uaArchiveInsert( *phArchive ) ) / insert new line in archiveprintf( InsertJobCB: error on updating archive rn );rc = FALSE ;return rc; The Change Job button sets the quantity for the specified job ID.Change_Job_Button_1.pdf ( 3 KB ) Button Change Job#include apdefap.hvoid OnClick(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)long presetValue = GetTagWord( PresetNumber );if( uaUtilityEnumRecords( JobData, ID0 , NULL , SetPartsNumberCB , &presetValue ) )printf( Preseting Values: O.K. rn );elseprintf( Preseting Values failed rn );Funktion SetPartsNumberCB#include apdefap.hBOOL SetPartsNumberCB( UAHARCHIVE* phArchive , void* pUserData )BOOL rc = TRUE ; / return codeif( ! uaArchiveSetFieldValueLong( *phArchive, 2 , *(long*)pUserData ) ) / write number of parts toarchiveprintf( SetPartsNumberCB: error on writing to Archive rn );rc = FALSE ;elseif( !uaArchiveUpdate( *phArchive ) ) / update archive lineprintf( SetPartsNumberCB: error on updating Archive rn );rc = FALSE ;return rc ; The Get Job with biggest Amount button provides the name for the job with the largest quantity specified.Get_biggestJob_Button_1.pdf ( 3 KB ) Button Get Job with biggest amount#include apdefap.hvoid OnClick(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)char productname100;if ( uaUtilityEnumRecords(JobData, NULL , Amount DESC , GetNameCB , productname ) )SetTagChar( ProductNameBiggestJob , productname );printf( Get Name O.K. rn ) ;elseprintf( Get Name failed rn ) ;Function GetNameCB#include apdefap.hBOOL GetNameCB( UAHARCHIVE* phArchive , void* pUserData )if( !uaArchiveMoveFirst( *phArchive ) ) return FALSE ;return uaArchiveGetFieldValueString( *phArchive, 1 , pUserData, 50 ); The Preset No. of Parts Amount button sets the specified amount for each job.Preset_No_of_PartsButton_1.pdf ( 3 KB ) Button Preset No. of Parts#include apdefap.hvoid OnClick(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)long id = GetTagDWord( ID ) ;long parts = GetTagWord( BlanksToProduce );char filter 20 ;sprintf( filter, ID=%d, id );if ( uaUtilityEnumRecords(JobData, filter, NULL , SetPartsNumberCB, &parts ) )printf( Update Job: O.K rn