CodeTransfer

VBComponents.Import stays quiet when the target already carries a component of that name: VBA imports the arriving one under a second name and keeps both copies, and the project stops compiling. Every transfer therefore removes the component that is already there before it imports, and files a warning through Checking naming it. The source copy is the one that survives, and a template author who wants their own code kept gives it another name. Owner decision, 2026-07-31.

Every member of this class reads a workbook's VBProject. Excel refuses that read with error 1004 while "Trust access to the VBA project object model" is off, and that is how a fresh install ships. SourceProject and TargetProject raise ErrorUnexpectedState naming the setting. Component lookups happen after that read, where a Nothing means the component is missing.

Writing code into a component empties it first. The four writers keep the text they are about to replace and put it back when the write raises, so a failure leaves the target holding what it held before.

Entries filed here leave through HasCheckings and CheckingValues. Linelist keeps the instance after Prepare, and clickGenerate flushes the entries into the generation report.

Depends on: TemporaryRepos, Checking

Version: 1.1 (2026-07-31)

Create #

create

Create a CodeTransfer instance

Signature:

Public Function Create(ByVal sourceWkb As Workbook, _
                       ByVal targetWkb As Workbook, _
                       ByVal tempRepos As TemporaryRepos) As CodeTransfer

Factory method and Friend bindings for construction.

Creates a new CodeTransfer wired to transfer components from sourceWkb to targetWkb using tempRepos for intermediate file storage. All three parameters are validated as non-Nothing, and the instance is sealed before it is handed back, so the three bindings hold for its whole life.

Parameters:

• sourceWkb: Workbook. The workbook containing the VBA components to export.
• targetWkb: Workbook. The workbook that will receive the imported components.
• tempRepos: TemporaryRepos. The temporary file repository for export/import.

Returns: CodeTransfer. A fully initialised instance ready for transfers.

Throws:

• ProjectError.ObjectNotInitialized When any parameter is Nothing.

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Seal #

seal

Close the instance to creation-only writes

Signature:

Public Sub Seal()

Called by the factory once the three bindings are in place. Swapping the target workbook part way through a transfer would scatter components across two files, so the setters refuse a second write.

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TransferClass #

transfer-class

Transfer a class module from source to target workbook

Signature:

Public Sub TransferClass(ByVal className As String)

Public methods for transferring VBA components.

Exports the named class module to a file called after the component, imports it into the target workbook, and deletes the file. A class of that name already in the target is removed first and the removal is filed through Checking.

Parameters:

• className: String. The VBA component name of the class to transfer.

Throws:

• ProjectError.ElementNotFound When the source workbook has no such class.

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TransferModule #

transfer-module

Transfer a standard module from source to target workbook

Signature:

Public Sub TransferModule(ByVal moduleName As String)

Exports the named standard module to a file called after the component, imports it into the target workbook, and deletes the file. A module of that name already in the target is removed first and the removal is filed through Checking.

Parameters:

• moduleName: String. The VBA component name of the module to transfer.

Throws:

• ProjectError.ElementNotFound When the source workbook has no such module.

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TransferForm #

transfer-form

Transfer a UserForm from source to target workbook

Signature:

Public Sub TransferForm(ByVal formName As String)

Exports the named UserForm to a .frm and a .frx called after the component, imports it into the target workbook, and deletes both files. A form of that name already in the target is removed first and the removal is filed through Checking. The .frx path is built by swapping the extension, which is what the VBIDE writes beside the .frm.

Parameters:

• formName: String. The VBA component name of the form to transfer.

Throws:

• ProjectError.ElementNotFound When the source workbook has no such form.

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TransferWorkbookCode #

transfer-workbook-code

Copy code from a source module into the target's ThisWorkbook component

Signature:

Public Sub TransferWorkbookCode(ByVal moduleName As String)

Reads all code lines from the named module in the source workbook and writes them into the target workbook's ThisWorkbook code module, replacing what is there. The component is reached through Workbook.CodeName, which is where a workbook's own event code lives. The previous text is put back when the write raises.

Parameters:

• moduleName: String. The source module whose code will be copied.

Throws:

• ProjectError.ElementNotFound When the source workbook has no such module.

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TransferWorksheetCode #

transfer-worksheet-code

Copy code from a source module into a worksheet's code module

Signature:

Public Sub TransferWorksheetCode(ByVal moduleName As String, ByVal targetSheetName As String)

Reads all code lines from the named module in the source workbook and writes them into the code module of the worksheet identified by targetSheetName in the target workbook, replacing what is there. The worksheet is looked up by its user-visible Name and its CodeName then locates the VBComponent, because the caller passes translated sheet names. Used to inject event handlers such as Worksheet_SelectionChange during linelist generation. The previous text is put back when the write raises.

Parameters:

• moduleName: String. The source module whose code will be copied.
• targetSheetName: String. The user-visible name of the worksheet in the target workbook whose code module will receive the code.

Throws:

• ProjectError.ElementNotFound When the source module does not exist.
• ProjectError.ElementNotFound When the target worksheet does not exist.

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CopyModuleText #

copy-module-text

Copy code text from a source module to an existing target module

Signature:

Public Sub CopyModuleText(ByVal moduleName As String)

Reads all code from the named module in the source workbook and writes it into the same-named module in the target workbook, replacing what is there. Both workbooks have to carry the module already: this member writes text into a component and creates none. Linelist calls it on the template branch, where the target workbook arrives with its own ribbon module. The previous text is put back when the write raises.

Parameters:

• moduleName: String. The module name. It has to exist in both workbooks.

Throws:

• ProjectError.ElementNotFound When either workbook lacks the module.

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HasCheckings #

has-checkings

Whether anything was filed during the transfers

Signature:

Public Property Get HasCheckings() As Boolean

The Checking entries this instance filed, and how a caller reads them.

Returns: Boolean. True once one entry has been recorded.

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CheckingValues #

checking-values

The diagnostic log of the transfers

Signature:

Public Property Get CheckingValues() As Object

Answers the internal Checking object holding every entry filed by this instance, and Nothing while none has been filed. The GenerationLog takes it through Linelist.

Returns: Object. A Checking instance, or Nothing.

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HasSourceComponent #

has-source-component

Whether the source workbook carries one component

Signature:

Public Function HasSourceComponent(ByVal componentName As String) As Boolean

For a component that is being added to the project and is not in every designer yet. The caller transfers it when it is there and files a note when it is not, so one designer without it still generates a linelist.

Parameters:

• componentName: String. The component name to look for.
• componentName: String. The component to look for.

Returns: Boolean. True when the source workbook carries it.

Throws:

• ProjectError.ElementNotFound When the source workbook has no such component.

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