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 WINDEVWEBDEV AND WINDEV MOBILE

Version: 2025

Analysis: Description of data file structure
The analysis allows you to define the structure of data files used by the project...
How do I run through a data file?
Looper control linked to a data file
A Looper control can be used to display the content of a data file or query...
Creating an executable: Data file directory
Two types of directories can be configured when creating the executable...
Linking a Table control to a data file or query
A Table control can be used to display the content of a data file or query...
Generating a description of a data file from a window or from a page
When you design a quick prototype, you often create windows (or pages) without defining any data files...
HEndNoModif (Function)
Unlocks a file that was locked by the same program with HNoModif.
<Source>.ListKey (Function)
Returns the list of keys in a data file (query or view) recognized by the HFSQL engine.
<Source>.ExportXML (Function)
Exports the records found in a data file (HFSQL or OLE DB), view or query to an XML file.
HDescribeFullTextIndex (Function)
Describes a full-text index of data file created programmatically.
HExportJSONString (Function)
Exports the records from a data file (HFSQL or OLE DB), view or query to a JSON string.
HWatchStop (Function)
Stops watching a data file on an HFSQL server.
HExportCSV (Function)
Exports the records found in a data file (HFSQL or OLE DB), a view or a query to a CSV file.
<Source>.Watch (Function)
Trigger monitoring of write actions (add, modify or delete) performed on a data file present on an HFSQL server. In case of modification, a specific procedure can be triggered.
HErrorLock (Function)
Used to check whether a lock error occurred.
<Source>.Read (Function)
Reads a record in a file according to a given record number.
HNoModif (Function)
Forbids all the modifications on a data file (for all the programs, including the one that requested the no-modification policy).
HRestorePosition (Function)
Restores the previously saved context of a file (function HSavePosition): record in progress, filter, playback pointers.
HDescribeFile (Function)
Describes a data file programmatically.
<Source>.ExportCSV (Function)
Exports the records found in a data file (HFSQL or OLE DB), a view or a query to a CSV file.
HListSpatialKeys (Function)
Returns the spatial keys of a data file (used in a query or view) recognized by the HFSQL engine.
<Source>.DescribeFile (Function)
Describes a data file programmatically.
HErrorPassword (Function)
After the execution of a read or write function in a data file, used to find out whether an error caused by a wrong password occurred on this data file.
Using Unicode in HFSQL data files
The analysis proposes two types of Unicode items...
<Source>.DeleteAll (Function)
Deletes all records from a data file, an HFSQL view or a query.
HDelete (Function)
Deletes a record from a data file (query or view).
HClose (Function)
Closes either a data file or all data files opened by the current user: all corresponding physical data files are closed for the current user.
<Source>.Previous (Function)
Sets the position on the previous record of the data file according to a browse item.
HDescribeItem (Function)
Describes a file item programmatically.
<Source>.Delete (Function)
Deletes a record from a data file (query or view).
HFTListWord (Function)
Lists the words of the current record that will be taken into account by the full-text indexing.
HDeactivateTrigger (Function)
Disables a trigger.
HUnlockRecNum (Function)
Unlocks a record locked by:
  • HLockRecNum,
  • a read function used with a locking parameter (HRead associated with the hLockWrite or hLockReadWrite constant for example).
Managing connections
WINDEV, WEBDEV and WINDEV Mobile propose different methods for describing a connection...
<Source>.NoModif (Function)
Forbids all the modifications on a data file (for all the programs, including the one that requested the no-modification policy).
<Source>.ExportXLS (Function)
Exports records from a data file (HFSQL or OLE DB), view or query to an Excel file (XLSX).
<Source>.Filter (Function)
Defines and enables a filter on a data file, view or query.
HFirst (Function)
Sets the position on the first record of a data file according to the specified browse item.
HRecordToString (Function)
Converts the content of the current record to string (in a data file, HFSQL view, query, etc.).
<Source>.Open (Function)
Opens a data file.
HGetCurrentPosition (Function)
Returns the approximate position of current record in the data file.
<Source>.Last (Function)
Sets the position on the last record of a data file according to a browse item.
HRead (Function)
Reads a record in a file according to a given record number.
HReadNext (Function)
Sets the position on the next data file record according to a browse item.
HLast (Function)
Sets the position on the last record of a data file according to a browse item.
<Source>.Write (Function)
Writes a record into a data file without updating the indexes corresponding to all keys used in the file.
HFilter (Function)
Defines and enables a filter on a data file, view or query.
HDBCreation (Function)
Ends the description of the structure of an xBase data file programmatically.
<Source>.RestorePosition (Function)
Restores the previously saved context of a file (function HSavePosition): record in progress, filter, playback pointers.
HOut (Function)
Used to find out whether the record on which you want to be positioned is located outside the data file, filter, view or query.
HReadLast (Function)
Sets the position on the last record of a data file according to a browse item.
HExportJSON (Function)
Exports the records found in a data file (HFSQL or OLE DB), view or query to a JSON file.
<Source>.CreateView (Function)
Creates an HFSQL view.
This function uses the former view mechanism.
<Source>.GetCurrentPosition (Function)
Returns the approximate position of current record in the data file.
HWatch (Function)
Trigger monitoring of write actions (add, modify or delete) performed on a data file present on an HFSQL server. In case of modification, a specific procedure can be triggered.
<Source>.SavePosition (Function)
Stores the current context of a data file: current record, filter, read pointers.
<Source>.ReadNext (Function)
Sets the position on the next data file record according to a browse item.
HCheckUnaltered (Function)
Checks that one or all records in an unalterable data file have not been modified (e.g. with a hexadecimal editor).
<Source>.ListLink (Function)
Returns the list of links (Merise) in the current analysis or in a specific analysis.
HDeleteAll (Function)
Deletes all records from a data file, an HFSQL view or a query.
<Source>.ListSynonym (Function)
Returns the list of synonyms used by a full-text index.
HListItem (Function)
Returns the list of items:
  • found in a data file ( a query or a view) known to the HFSQL engine. The data files defined by HDeclare, HDeclareExternal and HDescribeFile are taken into account.
  • found in a Record variable.
HCancelAlias (Function)
Cancels an alias that was declared beforehand by HAlias.
HListWatchedFiles (Function)
Returns the list of data files watched by HWatch.
<Source>.ListFullTextIndex (Function)
Returns the list of full-text indexes of a file (a query or a view) recognized by the HFSQL engine.
<Source>.Next (Function)
Sets the position on the next data file record according to a browse item.
Zombie data files and items
During the life of an application, items live and die...
<Source>.First (Function)
Sets the position on the first record of a data file according to the specified browse item.
Unalterable data files
This feature is used to signal that a data file cannot be modified after writing...
HSavePosition (Function)
Stores the current file context (current record, filter, pointers).
HErrorIntegrity (Function)
Used to check whether an integrity error occurred.
<Source>.ReadLast (Function)
Sets the position on the last record of a data file according to a browse item.
<Source>.DeleteView (Function)
Deletes a previously created view. This function uses the former view mechanism.
<Source>.DescribeTrigger (Function)
Adds or modifies a trigger on an HFSQL data file.
<Source>.EndNoModif (Function)
Unlocks a file that was locked by the same program with HNoModif.
<Source>.RetrieveRecord (Function)
Returns the content of the current record (in a file, a view or a query, ...).
HListREP (Function)
Returns the list of assignments for the data files handled by the current application, which means the list of physical files corresponding to the files described in the analysis.
HSetPosition (Function)
Sets the position on a record, based on the approximate position of one of its items.
<Source>.FTListWord (Function)
Lists the words of the current record that will be taken into account by the full-text indexing.
<Source>.ListItem (Function)
Returns the list of items in a data file (query or view) recognized by the HFSQL engine. The data files defined by HDeclare, HDeclareExternal and HDescribeFile are taken into account.
<Source>.ReadPrevious (Function)
Sets the position on the previous record of a file according to a browse item.
HReset (Function)
Initializes:
  • one or all variables of file items with their default values.
  • one or all items of a Record variable with their default values.
HDeactivateFilter (Function)
Temporarily disables the filter on a data file (view or query).
HExportXLS (Function)
Exports records from a data file (HFSQL or OLE DB), view or query to an Excel file (XLSX).
HOpen (Function)
Opens a data file.
<Source>.ExportJSON (Function)
Exports the records found in a data file (HFSQL or OLE DB), view or query to a JSON file.
<Source>.ListStopWord (Function)
Returns the list of stop words used by a full-text index.
HListFullTextIndex (Function)
Returns the list of full-text indexes of a file (a query or a view) recognized by the HFSQL engine.
<Source>.WatchStop (Function)
Stops watching a data file on an HFSQL server.
<Source>.UnlockFile (Function)
Unlocks the records of a data file:
  • locked by HLockFile.
  • individually locked by a locking read function.
HWrite (Function)
Writes a record into a data file without updating the indexes corresponding to all keys used in the file.
<Connection variable>.ListWatchedFiles (Function)
Returns the list of data files watched by HWatch.
HCreateView (Function)
Creates an HFSQL view.
This function uses the former view mechanism.
<Source>.ExportJSONString (Function)
Exports the records from a data file (HFSQL or OLE DB), view or query to a JSON string.
HListLink (Function)
Returns the list of data file bindings (Merise type) present:
  • in the current analysis,
  • in ongoing analyses (projects with multiple analyses).
  • in a specific analysis.
HDeleteView (Function)
Deletes a previously created view. This function uses the former view mechanism.
HListKey (Function)
Returns the list of keys in a data file (query or view) recognized by the HFSQL engine.
<Source>.Reset (Function)
Initializes:
  • one or all variables of file items with their default values.
  • one or all items of a Record variable with their default values.
HDescribeTrigger (Function)
Adds or modifies a trigger on an HFSQL data file.
NULL values in HFSQL
WINDEV, WEBDEV and WINDEV Mobile allow you to manage the NULL value in the items of the HFSQL data files and for all the other types of accesses (Native, OLE DB, ...
HPrevious (Function)
Sets the position on the previous record of the data file according to a browse item.
<Source>.Found (Function)
Checks whether the current record corresponds to the current filter or search.
HFound (Function)
Checks whether the current record corresponds to the current filter or search.
HUnlockFile (Function)
Unlocks the records of a data file:
  • locked by HLockFile.
  • individually locked by a locking read function.
HDescribeLink (Function)
Describes a link between two data files programmatically.
HRetrieveRecord (Function)
Returns the content of the current record (in a file, a view or a query, ...).
HReadPrevious (Function)
Sets the position on the previous record of a file according to a browse item.
HListSynonym (Function)
Returns the list of synonyms used by a full-text index.
Application triggers
A trigger is a WLanguage procedure automatically called by the HFSQL engine whenever a modification is performed (addition, deletion, modification, ...) on a record of a data file.
<Source>.DeactivateFilter (Function)
Temporarily disables the filter on a data file (view or query).
<Source>.CheckUnaltered (Function)
Checks that one or all records in an unalterable data file have not been modified (e.g. with a hexadecimal editor).
HListFile (Function)
Returns the list of files:
  • current analysis.
  • analyses in progress (projects with multiple analyses).
  • a specific analysis recognized by the HFSQL engine.
  • available on a connection via a Native Connector or an OLE DB driver.
  • for a group of files defined in the data model editor.
<Source>.Close (Function)
Closes either a data file or all data files opened by the current user: all corresponding physical data files are closed for the current user.
<Source>.Out (Function)
Allows you to find out whether the record on which you want to be positioned is located outside the data file, filter, view or query.
<Source>.RecordToString (Function)
Converts the content of the current record to string (in a data file, HFSQL view, query, etc.).
<Source>.UnlockRecNum (Function)
Unlocks a record locked by:
  • HLockRecNum,
  • a read function used with a locking parameter (HRead associated with the hLockWrite or hLockReadWrite constant for example).
HExportXML (Function)
Exports the records found in a data file (HFSQL or OLE DB), view or query to an XML file.
<Source>.ListSpatialKeys (Function)
Returns the spatial keys of a data file (used in a query or view) recognized by the HFSQL engine.
<Source>.SetPosition (Function)
Sets the position on a record, based on the approximate position of one of its items.
HNext (Function)
Sets the position on the next data file record according to a browse item.
<DiskFile variable>.ChangeSize (Function)
Resizes an external file.
<Variable DiskFile>Create (Function)
Creates an external file.
fChangeSize (Function)
Resizes an external file.
Uploading files
Uploading consists in saving a file located on the user's computer to the Web server......
Modbus
Modbus is a "field" (industrial and/or restricted environments) communication protocol created in 1979......
JSONExecute (Function)
Calls a server URL that returns data in JSON format (JavaScript Object Notation).
Heatmap chart
The Heatmap chart is used to represent in 2 dimensions data with 3 axes of values......
Telemetry: Method used to send data
Telemetry data is sent to the server regularly and is processed by the server every 2 hours......
SourceDescription (Property)
The SourceDescription property is used to get the name of the element used as data source of a series.
grColumnSpacing (Function)
Indicates the spacing between each data category in a column chart or in a Minimum/Maximum stock chart....
<Chart>.ColumnSpacing (Function)
Indicates the spacing between each data category in a column chart or in a Minimum/Maximum stock chart....
SchedulerPosition (Function)
Displays a Scheduler control from a specified date or returns the date of the first day (or last day) displayed in a Scheduler control.
SchedulerPositionDateTime
Displays a Scheduler control from a specified date or returns the date of the first day (or last day) displayed in a Scheduler control.
<Scheduler>.PositionDateTime (Function)
Displays a Scheduler control from a specified date or returns the date of the first day (or last day) displayed in a Scheduler control.
Query: Displaying the records corresponding to a given period
When a "Date" item is found in the query, you have the ability to only select the records corresponding to a given period......
LastDayOfMonth (Function)
Returns the date of the last day for the specified month.
FirstDayOfYear (Function)
Returns the date of the first day of the year.
IntegerToDate (Function)
Converts an integer into a date in YYYYMMDD format.
<Date type>.ToDay (Function)
Returns the day that corresponds to a given date.
CalculatedItemExpression (Property)
The CalculatedItemExpression property is used to: Find out the SQL expression that defines the value of a calculated item. This item was defined in the data model editor or through programming. Define the SQL expression returning the value of a calculated item (when describing the item through programming)....
CalculatedDefaultValue (Property)
The CalculatedDefaultValue property is used to: Find out the SQL expression that defines the default value of an item. This item was defined in the data model editor or through programming. Define the SQL expression that returns the default value of an item (item described through programming only)....
The Edit control
The Edit control allows users to enter data......
DateToDay (Function)
Returns the day that corresponds to a given date.
fSelect (Function)
Opens the Windows file picker.
NetRenameFile (Function)
Renames or moves a file located on the FTP (File Transfer Protocol) or RPC (Remote Procedure Call) server created with WINDEV. This function is kept for backward compatibility....