# Dynamic Template Generation > Build a Visual Basic 6 mail merge layout editor: insert fields of any database into a template, create labels at run time and save the database name with Save. - **Product:** TX Text Control ActiveX - **Section:** Documentation - **Kind:** Topic - **Path:** TX Text Control ActiveX > Mail Merge > Dynamic Template Generation - **1531 words** - **Web URL:** https://docs.textcontrol.com/tx-text-control-activex/mail-merge/dynamic-templates/ - **LLMs URL:** https://docs.textcontrol.com/tx-text-control-activex/mail-merge/dynamic-templates/llms.txt - **LLMs-Full URL:** https://docs.textcontrol.com/tx-text-control-activex/mail-merge/dynamic-templates/llms-full.txt --- The third part of the Visual Basic mail merge sample turns the application into a mail merge layout editor. The user selects a database and inserts its fields into the active document with mouse clicks. When the mail merge starts, these fields are replaced by the data from the database. The application doesn't know in advance how many fields a database has, so it must work with databases of varying size. Every piece of static code that deals with database fields is replaced by code that uses the field names at run time. The project files of this part are in the *Samples\\vb6\\MailMerge\\Step3* directory. ### Select a Database A menu item opens a Common Dialog in which the user selects a database. The database isn't loaded: only its name is stored in the `curDBName` variable. Holding an entire database in memory could cause problems when it is several terabytes in size. ### Insert Database Fields Into the Template The user may insert only fields that exist in the database into the active document. For this, the form has a combo box, which is filled with the field names of the database when the database is loaded. A button inserts the field selected in the combo box into the active document. ### Create the Labels of the Browse Database Form In the previous part, the labels of the *Browse Database* form that display the data were statically linked to the database. Now they are a control array: the labels are created when the form is loaded and then linked to the corresponding database field. The `Form_Load` event procedure of the form does this: ```vbscript Private Sub Form_Load() Data1.DatabaseName = curDBName doPrint = False TXHidden.Left = 10000 ' Move TX out of the visible area Dim db As Database Dim rs As Recordset ' Find record Set db = OpenDatabase(curDBName) Set rs = db.OpenRecordset(db.TableDefs(0).name) lblField(0).Caption = rs.Fields(0).name lblData(0).DataField = rs.Fields(0).name ' Create labels For i = 1 To rs.Fields.Count - 1 Load lblField(i) lblField(i).Top = 320 + (i * 300) lblField(i).Caption = rs.Fields(i).name lblField(i).Visible = True Load lblData(i) lblData(i).Top = 320 + (i * 300) lblData(i).DataField = rs.Fields(i).name lblData(i).Visible = True ' if i > 6 We need more space If i > 6 Then Form2.Height = Form2.Height + 300 Frame1.Height = Frame1.Height + 300 Data1.Top = Data1.Top + 300 cmdMerge.Top = cmdMerge.Top + 300 cmdCancel.Top = cmdCancel.Top + 300 End If Next i End Sub ``` The code works as follows: - The data control `Data1` is connected to the database named in `curDBName`, and the hidden `TXTextControl` of the print queue is moved out of the visible area. - The field labels, `lblField`, show the names of the database fields. The data labels, `lblData`, display the content from the database. - For each further field of the database, the loop loads a new field label and a new data label and places them below the previous ones. - As soon as the database has more than seven fields, the form, its frame, the data control and the **Merge** and **Cancel** buttons are enlarged or moved, so that there is enough room for all labels. ### Save the Database Name With the Template When the fields of a database appear in the active document, the connected database must be loaded with the document. Therefore, the name of the database is saved in the document: the application writes a header to the file first, and only then saves the data of the `TXTextControl`. On loading, the header is read first. The following code saves a template this way: ```vbscript Private Sub mnuSaveTemplate_Click() Dim FileID As Long Dim lFilePos As Long On Error Resume Next ' Create a "Save File" dialog box CommonDialog1.Filter = "TX Demo (*.ttx)|*.ttx" CommonDialog1.DialogTitle = "Save As" CommonDialog1.Flags = cdlOFNOverwritePrompt Or cdlOFNHideReadOnly CommonDialog1.CancelError = True CommonDialog1.ShowSave If Err Then Exit Sub ' Write Header Open CommonDialog1.FileName For Binary As #1 FileID = FILE_ID Put #1, , FileID Put #1, , curDBName Put #1, , vbCrLf lFilePos = loc(1) Close #1 TXTextControl1.Save CommonDialog1.FileName, lFilePos, 3 End Sub ``` The code works as follows: - A **Save As** dialog box asks for the file name of the template, with the filter *\*.ttx*. If the user cancels it, the procedure ends. - The header, a file ID, the database name in `curDBName` and a line break, is written to the file, and `lFilePos` receives the position after it. - [Save](https://docs.textcontrol.com/tx-text-control-activex/reference/txtextcontrol/save-method/llms-full.txt) writes the document to the same file at the position `lFilePos`, in the internal TX Text Control format (3). ### Next Steps - [Printing More Than One Record](https://docs.textcontrol.com/tx-text-control-activex/mail-merge/multiple-records/llms-full.txt): the print queue and the hidden `TXTextControl` this part builds on. - [Connecting to Databases](https://docs.textcontrol.com/tx-text-control-activex/mail-merge/databases/llms-full.txt): store a complete document in a database field. - [Marked Text Fields](https://docs.textcontrol.com/tx-text-control-activex/document-editor/fields/llms-full.txt): the fields that receive the database data. --- ## Nearby - **Previous:** [Printing More Than One Record](https://docs.textcontrol.com/tx-text-control-activex/mail-merge/multiple-records/llms-full.txt) - **Next:** [Connecting to Databases](https://docs.textcontrol.com/tx-text-control-activex/mail-merge/databases/llms-full.txt)