pyzwcadmech Documentation

pyzwcadmech is a lightweight Python wrapper for the ZWCAD MFG COM API. It prefers dynamic COM calls first and uses the ZwmToolKit type library only as a compatibility enhancement when available.

For compatibility with recent changes, the distribution also includes the pyzwcadm package alias, while the primary package name is pyzwcadmech.

1. Requirements

• OS: Windows
• Software Dependency: A licensed installation of ZWCAD MFG
• Python Environment: Python 3.x
• Third-party Libraries: comtypes

  pip install comtypes
  

• Type Library Note: ZwmToolKit.tlb is optional. The library first tries to connect to the registered mechanical COM interfaces. If the type library is available, it can improve compatibility for a few complex calls.

2. Directory Structure

Recommended project layout:

your_project_directory/
├── ZwmToolKit.tlb       # Optional COM type library for compatibility enhancement
├── pyzwcadmech/
│   ├── __init__.py
│   └── api.py
└── hello_mech.py

3. Quick Start

from pyzwcadmech import ZwCADMech


def main():
    mech = ZwCADMech()
    mech.open_file("")

    title = mech.get_title()
    if title:
        print("Successfully obtained the title block object!")
        for i in range(title.get_item_count()):
            label, name, value = title.get_item(i)
            print(f"{label}: {value}")

    mech.close()


if __name__ == "__main__":
    main()

How to run the examples:

• Install dependencies: pip install pyzwcadmech and pip install PyQt5
• Install ZWCAD MFG on the machine
• Run a script from examples, for example python pyqt_ZWM_example_en.py
• In most cases you do not need to manually copy ZwmToolKit.tlb

4. API Reference

4.1 ZwCADMech

mech = ZwCADMech(cad_app=None)

• cad_app: Optional existing ZWCAD.Application instance
• mech.app: Native ZWCAD.Application COM object
• mech.zwm_app: ZwmApp wrapper instance
• mech.zwm_db: ZwmDb wrapper instance

Shortcut methods delegated to ZwmDb:

• open_file(filepath: str)
• save(flag: int = 33)
• close()
• get_title() -> ZwmTitle
• get_bom() -> ZwmBom
• get_frame() -> ZwmFrame
• title_edit(), total_bom_edit(), frame_edit(), fjl_edit()

4.2 ZwmTitle

• get_item_count() -> int
• get_item(index: int) -> tuple(str, str, str)
• set_item(key: str, value: str)

4.3 ZwmBom and ZwmBomRow

ZwmBom:

• get_item_count() -> int
• get_item(index: int) -> ZwmBomRow
• set_item(index: int, bom_row: ZwmBomRow)
• add_item(bom_row: ZwmBomRow)
• insert_item(index: int, bom_row: ZwmBomRow)
• delete_item(index: int)
• create_bom_row() -> ZwmBomRow

ZwmBomRow:

• get_item_count() -> int
• get_item(index: int) -> tuple(str, str, str)
• set_item(key: str, value: str)

4.4 ZwmFrame

ZwmFrame exposes frame properties directly through Python properties, including:

• width, height, std_name, frame_size_name, orientation, scale1, scale2
• frame_style_name, title_style_name, bom_style_name, dhl_style_name, fjl_style_name, csl_style_name, ggl_style_name
• have_dhl, have_fjl, have_btl, have_csl, have_ggl

After editing properties, call mech.zwm_db.build_frame(511) or refresh_frame() to apply the changes.

4.5 ZwmDb

Additional database methods:

• switch_frame(frame_name: str)
• get_frame_count() -> int
• get_frame_name(index: int) -> str
• get_next_frm_name() -> tuple(ZwmFrame, str)
• refresh_title(), refresh_bom(), refresh_frame()
• build_frame(switch_type: int = 511)

5. FAQ

Q: Do I need ZwmToolKit.tlb to use the library?
A: Usually no. pyzwcadmech now prefers dynamic COM calls first. The type library is mainly used to improve compatibility for a few complex interface calls.

Q: I see Failed to load ZwmToolKit.tlb or ModuleNotFoundError.
A: First make sure comtypes is installed and try connecting to ZWCAD MFG directly. If only a few complex calls fail, then add ZwmToolKit.tlb to your project directory or set PYZWCADMECH_TLB_PATH.

Q: I see Failed to create ZwmToolKit.ZwmApp.
A: This usually means either the standard ZWCAD edition is installed instead of the Mechanical edition, or the mechanical COM component is not registered correctly.

Q: get_title() or get_bom() returns None or raises an error.
A: Make sure mech.open_file("") was called successfully and that the current drawing actually contains the corresponding mechanical entities.

6. Packaging and Release

Recommended modern build flow:

python -m pip install --upgrade build twine
python -m build
python -m twine check dist/*
python -m twine upload dist/*