| LinkarClientUpdate Method |
Linkar Framework for .NET and Core
Update one or several records of a file, synchronously only.
Namespace: Linkar.Functions.PersistentAssembly: Linkar.Functions.Persistent (in Linkar.Functions.Persistent.dll) Version: 2.3.1
Syntax public string Update(
string filename,
string records,
UpdateOptions updateOptions = null,
DATAFORMAT_TYPE inputFormat = DATAFORMAT_TYPE.MV,
DATAFORMATCRU_TYPE outputFormat = DATAFORMATCRU_TYPE.MV,
string customVars = "",
int receiveTimeout = 0
)
Public Function Update (
filename As String,
records As String,
Optional updateOptions As UpdateOptions = Nothing,
Optional inputFormat As DATAFORMAT_TYPE = DATAFORMAT_TYPE.MV,
Optional outputFormat As DATAFORMATCRU_TYPE = DATAFORMATCRU_TYPE.MV,
Optional customVars As String = "",
Optional receiveTimeout As Integer = 0
) As String
public:
String^ Update(
String^ filename,
String^ records,
UpdateOptions^ updateOptions = nullptr,
DATAFORMAT_TYPE inputFormat = DATAFORMAT_TYPE::MV,
DATAFORMATCRU_TYPE outputFormat = DATAFORMATCRU_TYPE::MV,
String^ customVars = L"",
int receiveTimeout = 0
)
member Update :
filename : string *
records : string *
?updateOptions : UpdateOptions *
?inputFormat : DATAFORMAT_TYPE *
?outputFormat : DATAFORMATCRU_TYPE *
?customVars : string *
?receiveTimeout : int
(* Defaults:
let _updateOptions = defaultArg updateOptions null
let _inputFormat = defaultArg inputFormat DATAFORMAT_TYPE.MV
let _outputFormat = defaultArg outputFormat DATAFORMATCRU_TYPE.MV
let _customVars = defaultArg customVars ""
let _receiveTimeout = defaultArg receiveTimeout 0
*)
-> string
Parameters
- filename String
- Name of the file being updated.
- records String
- Buffer of record data to update. Inside this string are the recordIds, the modified records, and the originalRecords. Use StringFunctions.ComposeUpdateBuffer (Linkar.Strings library) function to compose this string.
- updateOptions UpdateOptions (Optional)
- Object with write options, including optimisticLockControl, readAfter, calculated, dictionaries, conversion, formatSpec, originalRecords.
- inputFormat DATAFORMAT_TYPE (Optional)
- Indicates in what format you wish to send the resultant writing data: MV, XML or JSON.
- outputFormat DATAFORMATCRU_TYPE (Optional)
- Indicates in what format you want to receive the data resulting from the Read, New, Update and Select operations: MV, XML, XML_DICT, XML_SCH, JSON, JSON_DICT or JSON_SCH.
- customVars String (Optional)
- Free text sent to the database allows management of additional behaviours in SUB.LK.MAIN.CONTROL.CUSTOM, which is called when this parameter is set.
- receiveTimeout Int32 (Optional)
- Maximum time in seconds that the client will wait for a response from the server. Default = 0 to wait indefinitely.
Return Value
StringThe results of the operation.
Remarks
Inside the records argument, the recordIds and the modified records always must be specified. But the originalRecords not always.
When
updateOptions argument is specified and the
OptimisticLockControl property is set to true, a copy of the record must be provided before the modification (originalRecords argument)
to use the Optimistic Lock technique. This copy can be obtained from a previous
Read(String, String, String, ReadOptions, DATAFORMAT_TYPE, DATAFORMATCRU_TYPE, String, Int32) operation. The database, before executing the modification,
reads the record and compares it with the copy in originalRecords, if they are equal the modified record is executed.
But if they are not equal, it means that the record has been modified by other user and its modification will not be saved.
The record will have to be read, modified and saved again.
See Also