- Vytvoril/a D2000 Dev Team, naposledy zmenil/a D2000 Doc Team dňa sep 29, 2024
%HI_RefreshData function
Function
The function %HI_RefreshData (Control functions) may be used:
- for displayer of Browser type - it updates displayed data. It also allows to change the selection condition or sorting of data.
- for displayer of Report type (containing the report of Crystal report type) - it sets the values of parameters, for which the function %HI_ReportPar was called.
Declaration
%HI_RefreshData( INT in refId [, TEXT in whereStr [, TEXT in orderByStr [, in par1[, in par2[, ...]]]]] ) BOOL %HI_RefreshDataSync( INT in refId [, TEXT in whereStr [, TEXT in orderByStr [, in par1[, in par2[, ...]]]]] )
Parameters
| refId | Reference to graphic object
(reference variable). |
| whereStr | SQL condition WHERE for selection limit of displayed data (for Browser type only). |
| orderByStr | SQL command ORDER for selection order control (sorting) (for Browser type only) |
| par1, par2, ... | List of constants or local variables that will be used instead of the parameters of parameterized SQL condition. |
Note
Condition and sorting can be also defined when you are configuring the graphic object in the process. These will be changed when the function %HI_RefreshData is called and displaying is updated. These parameters are not used for displayer of Report type.
The condition that has been changed by calling the function %HI_RefreshData may be parameterized. The parameterization makes the work with SQL database easy because the preparing (compilation) of parameterized SQL expression can be done only when changing the condition or sorting (i.e. text format of SQL expression). The proper setting of database parameters (e.g. Oracle: session_cached_cursors) enables to recycling the cursors (the compiled commands) between the callings of %HI_RefreshData.
The rules for the parameters:
The function %HI_RefreshDataSync waits on the selection according to new parameters and informs about the success of action by its value (@TRUE = successful execution, @FALSE = error). If the browser, which displays DB table, is configured so that it is initiated automatically (the parameter "Initial query" is ticked off), the function cannot be used in the initiate (BEGIN..END) part of the picture. In such case it returns @FALSE.
If a picture with a displayer of the Browser type has been resized and the displayer has dynamic number of lines depending on browser's height configured (see the parameter Lines), the function %HI_RefreshData must be called to refresh the current page with a changed number of lines.
The condition that has been changed by calling the function %HI_RefreshData may be parameterized. The parameterization makes the work with SQL database easy because the preparing (compilation) of parameterized SQL expression can be done only when changing the condition or sorting (i.e. text format of SQL expression). The proper setting of database parameters (e.g. Oracle: session_cached_cursors) enables to recycling the cursors (the compiled commands) between the callings of %HI_RefreshData.
The rules for the parameters:
- parameter refId must be always valid,
rules for whereStr and orderByStr:
Entered valid Empty or entered but invalid whereStr change of condition The last entered condition is valid (if it has not been entered, there is an empty string). orderByStr change of sorting The last entered sorting is valid (if it has not been entered, there is an empty string). - if par1 to parN are entered, their quantity must correspond to the condition (count #PAR#), however when changing the condition, they may not be omitted,
- if any of parameters from the range par1 to parN is invalid, it means NULL.
The function %HI_RefreshDataSync waits on the selection according to new parameters and informs about the success of action by its value (@TRUE = successful execution, @FALSE = error). If the browser, which displays DB table, is configured so that it is initiated automatically (the parameter "Initial query" is ticked off), the function cannot be used in the initiate (BEGIN..END) part of the picture. In such case it returns @FALSE.
If a picture with a displayer of the Browser type has been resized and the displayer has dynamic number of lines depending on browser's height configured (see the parameter Lines), the function %HI_RefreshData must be called to refresh the current page with a changed number of lines.
Example
%HI_RefreshData(_browser) ; updating (without changes in condition, sorting or parameters) %HI_RefreshData(_browser, "ID=21") ; changing the condition and updating %HI_RefreshData(_browser, "ID=21", "ID") ; changing the condition, sorting and updating
INT _cnt ; the local variable for the parameterized condition TEXT _name ; the local variable for the parameterized condition TEXT _INVALID = 1/0 ; auxiliary invalid constant of text type _cnt := 1 _name := "%SELF%" ; 1. change of condition (parameterized), sorting, parameters and updating %HI_RefreshData(_browser, "CNT=#PAR# AND NAME LIKE #PAR#", "NAME", _cnt, _name) _cnt := 2 _name := "%ODBC%" ; 2. just the change of parameters (recycling the SQL expression) and updating %HI_RefreshData(_browser, "CNT=#PAR# AND NAME LIKE #PAR#", "NAME", _cnt, _name) ; %HI_RefreshData(_browser, _INVALID, _INVALID, _cnt, _name) ; equivalent alternative to the writing by line above (if the condition has not been changed from the point 1) ; 3. without changes (recycling the SQL expression) and updating %HI_RefreshData(_browser, "CNT=#PAR# AND NAME LIKE #PAR#", "NAME", _cnt, _name) %HI_RefreshData(_browser) ; equivalent alternative to the writing by line above (it the condition, sorting and parameters have not been changed from point 2)
0 komentárov