CeSeekDatabase (RAPI) (Windows CE 5.0)
This function seeks the specified record in an open database.
CeSeekDatabase is a remote application interface (RAPI), which enables an application running on a desktop computer to make function calls on a Windows CE–based device.
CEOIDCeSeekDatabase(HANDLEhDatabase, DWORDdwSeekType, DWORDdwValue, LPDWORDlpdwIndex);
Parameters
- hDatabase
[in] Handle to the open database in which to seek. - dwSeekType
[in] Specifies the type of seek operation to perform. It is one of the values in the following table.Value Description CEDB_SEEK_CEOID Seeks until finding an object that has the specified object identifier. The dwValue parameter specifies the object identifier. This type of seek operation is very efficient. CEDB_SEEK_VALUESMALLER Starting from the current position, seeks backward toward the start of the sort. Always seeks backward, regardless of sort order. In ascending order, this finds the largest value smaller than the specified value; in descending order, this finds the smallest value larger than the specified value. If none of the previous records has a value that meets the search criteria, the seek pointer is left at the end of the database and the function returns 0. The dwValue parameter is a pointer to a CEPROPVAL structure.
CEDB_SEEK_VALUEFIRSTEQUAL Begins at the start of the sort and seeks forward until finding the first value that is equal to the specified value. Always seeks forward, regardless of sort order. If the seek operation fails, the seek pointer is left at the end of the database, and the function returns 0. The dwValue parameter is a pointer to a CEPROPVAL structure. CEDB_SEEK_VALUENEXTEQUAL Starting from the current seek position, seeks exactly one position forward in the sorted order and checks if the next record is equal in value to the specified value. If so, returns the object identifier of this next record; otherwise, returns 0 and leaves the seek pointer at the end of the database. This operation can be used in conjunction with the CEDB_SEEK_VALUEFIRSTEQUAL operation to enumerate all records with an equal value. The dwValue parameter is a pointer to a CEPROPVAL structure. . CEDB_SEEK_VALUEGREATER Starting from the current position, seeks backward toward the start of the sort. Always seeks forward, regardless of sort order. In ascending order this finds the smallest value greater than the specified value; in descending order this finds the largest value smaller than the specified value. If none of the following records has a value that meets the search criteria, the seek pointer is left at the end of the database and the function returns 0. The dwValue parameter is a pointer to a CEPROPVAL structure.
CEDB_SEEK_BEGINNING Seeks until finding the record at the specified position from the beginning of the database. The dwValue parameter specifies the number of records to seek from the beginning. CEDB_SEEK_CURRENT Seeks backward or forward from the current position of the seek pointer for the specified number of records. The dwValue parameter specifies the number of records to seek from the current position. The function seeks forward if dwValue is a positive value, or backward if it is negative. CEDB_SEEK_END Seeks backward for the specified number of records from the end of the database. The dwValue parameter specifies the number of records to seek from the end. - dwValue
[in] Specifies the value to use for the seek operation. The meaning of this parameter depends on the value of dwSeekType. - lpdwIndex
[out] Pointer to a variable that receives the index from the start of the database to the beginning of the record that was found. This parameter cannot be NULL.
Return Values
The object identifier of the record on which the seek ends indicates success. Zero indicates failure. To get extended error information a RAPI program, call CeGetLastError. CeGetLastError may return ERROR_INVALID_PARAMETER if a parameter is invalid.
Remarks
The CeSeekDatabase (RAPI) function always uses the current sort order as specified in the call to the CeOpenDatabase (RAPI) function. If the CEDB_AUTOINCREMENT flag was specified, an automatic seek of one from the current position is done with each read operation that occurs on the database.
A seek can only be performed on a sorted property value. After creating a database using CeCreateDatabase (RAPI) and opening the database using CeOpenDatabase (RAPI), subsequent calls to CeSeekDatabase (RAPI) assume the sort order that was specified in the propid parameter of the call to CeOpenDatabaseEx.
To enter negative values for the CEDB_SEEK_CURRENT case, cast a signed long. This changes the effective range on the record indexes to 31 bits from 32.
Multiple sort orders cannot be specified for a single property.
When a CEPROPVAL structure is required to seek, the propid parameter must be set to PROPID of the sort order specified in the CeOpenDatabaseEx (RAPI) call.
Requirements
OS Versions: Windows CE 1.01 and later.
Header: Rapi.h.
Link Library: Rapi.lib.
See Also
RAPI Functions | CeCreateDatabase (RAPI) | CeGetLastError | CeOpenDatabase (RAPI) | CeOpenDatabaseEx (RAPI) | CEPROPVAL
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