DBC转excel（python语言）

重复造轮子，只是为了熟悉一下DBC格式。
与同类工具的不同点：

1. 能批量转换在同一文件夹下的所有DBC，省时省力。
2. 很多同类工具转换后的excel列宽较小，不能直接显示全部信息。本代码使用了自适应的列宽，看起来更方便。**

# coding=UTF-8
import os
import argparse
import xlsxwriter as xw
import pandas as pd
import re
import openpyxl


# DBC信息解码，返回字典
def decode(str1):
    ans = {}
    # 报文帧
    if str1.startswith('BO_'):
        list1 = re.split(" |: |\n",str1)
        ans['message_id'],ans['message_name'],ans['message_size'],ans['transmitter'] = list1[1],list1[2],list1[3],list1[4]
        return ans
    # 信号帧
    elif str1.startswith(' SG_'):
        str1 = str1[5:] # 去掉" SG_ ",共5个字符
        ans['empty1'],ans['empty2'],ans['empty3'],ans['empty4'] = None,None,None,None

        sub = ':'
        spt = [sub.start() for sub in re.finditer(sub , str1)]
        ans['signal_name'],ans['multiplexer_indicator'] = re.split(" ",str1[0:spt[0]])[0], re.split(" ",str1[0:spt[0]])[1]
        str1 = str1[spt[0]+2:]

        sub = '@'
        spt = [sub.start() for sub in re.finditer(sub , str1)]
        ans['start_bit'],ans['signal_size'],ans['byte_order'],ans['value_type'] = str1[0: str1.find('|',0,spt[0])], str1[str1.find('|',0,spt[0])+1:spt[0]], str1[spt[0]+1], str1[spt[0]+2]
        if ans['byte_order'] == '0':
            ans['byte_order'] = 'intel'
        elif ans['byte_order'] == '1':
            ans['byte_order'] = 'motorola'
        if ans['value_type'] == '+':
            ans['value_type'] = '无符号数'
        elif ans['value_type'] == '-':
            ans['value_type'] = '有符号数'
        str1 = str1[spt[0]+4:]

        spt = str1.find(' ')
        ans['factor'],ans['offset'] = re.split(",",str1[1:spt-1])[0], re.split(",",str1[1:spt-1])[1]
        str1 = str1[spt+1:]

        sub = ']'
        spt = [sub.start() for sub in re.finditer(sub , str1)]
        ans['minimum'],ans['maximum'] = str1[1: str1.find('|',0,spt[0])], str1[str1.find('|',0,spt[0])+1:str1.find(']')]
        str1 = str1[spt[0]+2:]
        ans['unit'],ans['receiver'] = str1[0:str1.find(' ')], str1[str1.find(' ')+1:-2]

        return ans
    
    
if __name__ == '__main__':

    parser = argparse.ArgumentParser(description='将文件夹中的所有DBC文件转换为excel')
    parser.add_argument('dbc_dir', type=str,help='DBC文件所在的文件夹地址')
    parser.add_argument('excel_dir', type=str,help='excel的保存地址')
    parser.add_argument('excel_name', type=str,help='excel文件名')
    args = parser.parse_args()
    dbc_dir = args.dbc_dir
    excel_dir = args.excel_dir
    excel_name = args.excel_name

    title = ['message_id', 'message_name', 'message_size','transmitter', 'signal_name', 'multiplexer_indicator',
        'start_bit', 'signal_size', 'byte_order', 'value_type','factor', 'offset', 'minimum', 'maximum', 'unit', 'receiver']
    
    # 遍历指定文件夹下的DBC文件绝对路径，保存为list。
    dbcfiles = []
    for filename in os.listdir(dbc_dir):
        if filename.endswith('.dbc'):
            dbcfiles.append(filename)

    df = pd.DataFrame()
    df.to_excel(excel_name)

    for dbc in dbcfiles:
        # 将数据按表头顺序存入list
        with open(dbc_dir + '/' + dbc, 'r', encoding='gbk') as f:
            string = f.readlines()
        for i in string:
            data = decode(i)
            # data = translate(data)
            if data != None:
                val = list(data.values())
                df1 = pd.DataFrame([val])
                df = pd.concat([df,df1],axis=0)
    
        with pd.ExcelWriter(excel_name, mode='a', engine="openpyxl") as writer:
            df.to_excel(writer, sheet_name=dbc, header=title, index=False)

    workbook = openpyxl.load_workbook(excel_name)
    worksheet = workbook['Sheet1']
    workbook.remove(worksheet)
    for sheet_name in workbook.sheetnames:
        sheet = workbook[sheet_name]
        for column in sheet.columns:
            max_length = 0
            column = [cell for cell in column]
            for cell in column:
                try:
                    if len(str(cell.value)) > max_length:
                        max_length = len(cell.value)
                except:
                    pass
            adjusted_width = (max_length + 2)
            sheet.column_dimensions[column[0].column_letter].width = adjusted_width
    workbook.save(excel_dir+"\\"+excel_name)