本篇讲下如何使用纯python代码将excel 中的图表导出为图片。这里需要使用的模块有win32com、pythoncom模块。

网上经查询有人已经写好的模块pyxlchart，具体代码如下：

from win32com.client import Dispatch
import os
import pythoncom
class Pyxlchart(object):
 \"\"\"
 This class exports charts in an Excel Spreadsheet to the FileSystem
 win32com libraries are required.
 \"\"\"
 def __init__(self):
  pythoncom.CoInitialize()
  self.WorkbookDirectory = \'\'
  self.WorkbookFilename = \'\'
  self.GetAllWorkbooks = False
  self.SheetName = \'\'
  self.ChartName = \'\'
  self.GetAllWorkbookCharts = False
  self.GetAllWorksheetCharts = False
  self.ExportPath = \'\'
  self.ImageFilename = \'\'
  self.ReplaceWhiteSpaceChar = \'_\'
  self.ImageType = \'jpg\'
 def __del__(self):
  pass
 def start_export(self):
  if self.WorkbookDirectory == \'\':
   return \"WorkbookDirectory not set\"
  else:
   self._export()
 def _export(self):
  \"\"\"
  Exports Charts as determined by the settings in class variabels.
  \"\"\"
  excel = Dispatch(\"excel.application\")
  excel.Visible = False
  wb = excel.Workbooks.Open(os.path.join(self.WorkbookDirectory ,self.WorkbookFilename))
  self._get_Charts_In_Worksheet(wb,self.SheetName,self.ChartName)
  wb.Close(False)
  excel.Quit()
 def _get_Charts_In_Worksheet(self,wb,worksheet = \"\", chartname = \"\"):
  if worksheet != \"\" and chartname != \"\":
   sht = self._change_sheet(wb,worksheet)
   cht = sht.ChartObjects(chartname)
   self._save_chart(cht)
   return
  if worksheet == \"\":
   for sht in wb.Worksheets:
    for cht in sht.ChartObjects():
     if chartname == \"\":
      self._save_chart(cht)
     else:
      if chartname == cht.Name:
       self._save_chart(cht)
  else:
   sht = wb.Worksheets(worksheet)
   for cht in sht.ChartObjects():
    if chartname == \"\":
     self._save_chart(cht)
    else:
     if chartname == cht.Name:
      self._save_chart(cht)
 def _change_sheet(self,wb,worksheet):
  try:
   return wb.Worksheets(worksheet)
  except:
   raise NameError(\'Unable to Select Sheet: \' + worksheet + \' in Workbook: \' + wb.Name)
 def _save_chart(self,chartObject):
  imagename = self._get_filename(chartObject.Name)
  savepath = os.path.join(self.ExportPath,imagename)
  print savepath
  chartObject.Chart.Export(savepath,self.ImageType)
 def _get_filename(self,chartname):
  \"\"\"
  Replaces white space in self.WorkbookFileName with the value given in self.ReplaceWhiteSpaceChar
  If self.ReplaceWhiteSpaceChar is an empty string then self.WorkBookFileName is left as is
  \"\"\"
  if self.ImageFilename == \'\':
   self.ImageFilename == chartname
  if self.ReplaceWhiteSpaceChar != \'\':
   chartname.replace(\' \',self.ReplaceWhiteSpaceChar)
  if self.ImageFilename != \"\":
   return self.ImageFilename + \"_\" + chartname + \".\" + self.ImageType
  else:
   return chartname + \'.\' + self.ImageType
if __name__ == \"__main__\":
 xl = Pyxlchart()
 xl.WorkbookDirectory = \"\\\\\\\\maawtns01\\\\discipline\\\\procurement\\\\MATERIEL\\\\Raw Material\\\\Data Management\\\\Hawk\"
 xl.WorkbookFilename = \"Hawk Workability KPI.xlsm\"
 xl.SheetName = \"\"
 xl.ImageFilename = \"MyChart1\"
 xl.ExportPath = \"d:\\\\pycharts\"
 xl.ChartName = \"\"
 xl.start_export()
 print \"This file does not currently allow direct access\"
 print \"Please import PyXLChart and run start_export()\"

   
这里还使用Excel vba将chart另存为图片篇中创建的chart_column.xlsx表，使用上面的模块的方法如下：

from pyxlchart import Pyxlchart
xl = Pyxlchart()
xl.WorkbookDirectory = \"D:\\\\\"
xl.WorkbookFilename = \"chart_column.xlsx\"
xl.SheetName = \"\"
#xl.ImageFilename = \"MyChart1\"
xl.ExportPath = \"d:\\\\\"
xl.ChartName = \"\"
xl.start_export()

由于有该表里有多张图表，所以上面未指定xl.ImageFilename ，使用示例如下：

Excel vba将chart另存为图片
python下使用xlswriter模块，可以轻松在excel 中创建图片，不过想实现将生成的chart图表导出为图片，在email 中导入图片的目标 。经网上查询未找到通过python代码将excel 中已经生成的图片导出为图片的方法，不过通过变通方法，使用excel 内的vba 宏却可以轻松将图片导出。

1、导出单张图片

python 创建chart图片代码：

#coding: utf-8
import xlsxwriter
import random
def get_num():
 return random.randrange(0, 201, 2)
workbook = xlsxwriter.Workbook(\'analyse_spider.xlsx\') #创建一个Excel文件
worksheet = workbook.add_worksheet() #创建一个工作表对象
chart = workbook.add_chart({\'type\': \'column\'}) #创建一个图表对象
#定义数据表头列表
title = [u\'业务名称\',u\'星期一\',u\'星期二\',u\'星期三\',u\'星期四\',u\'星期五\',u\'星期六\',u\'星期日\',u\'平均流量\']
buname= [u\'运维之路\',u\'就要IT\',u\'baidu.com\',u\'361way.com\',u\'91it.org\'] #定义频道名称
#定义5频道一周7天流量数据列表
data = []
for i in range(5):
 tmp = []
 for j in range(7):
  tmp.append(get_num())
 data.append(tmp)
format=workbook.add_format() #定义format格式对象
format.set_border(1) #定义format对象单元格边框加粗(1像素)的格式
format_title=workbook.add_format() #定义format_title格式对象
format_title.set_border(1) #定义format_title对象单元格边框加粗(1像素)的格式
format_title.set_bg_color(\'#cccccc\') #定义format_title对象单元格背景颜色为
          #\'#cccccc\'的格式
format_title.set_align(\'center\') #定义format_title对象单元格居中对齐的格式
format_title.set_bold() #定义format_title对象单元格内容加粗的格式
format_ave=workbook.add_format() #定义format_ave格式对象
format_ave.set_border(1) #定义format_ave对象单元格边框加粗(1像素)的格式
format_ave.set_num_format(\'0.00\') #定义format_ave对象单元格数字类别显示格式
#下面分别以行或列写入方式将标题、业务名称、流量数据写入起初单元格，同时引用不同格式对象
worksheet.write_row(\'A1\',title,format_title)
worksheet.write_column(\'A2\', buname,format)
worksheet.write_row(\'B2\', data[0],format)
worksheet.write_row(\'B3\', data[1],format)
worksheet.write_row(\'B4\', data[2],format)
worksheet.write_row(\'B5\', data[3],format)
worksheet.write_row(\'B6\', data[4],format)
#定义图表数据系列函数
def chart_series(cur_row):
 worksheet.write_formula(\'I\'+cur_row, \\
  \'=AVERAGE(B\'+cur_row+\':H\'+cur_row+\')\',format_ave) #计算（AVERAGE函数）频
               #道周平均流量
 chart.add_series({
  \'categories\': \'=Sheet1!$B$1:$H$1\', #将“星期一至星期日”作为图表数据标签(X轴)
  \'values\':  \'=Sheet1!$B$\'+cur_row+\':$H$\'+cur_row, #频道一周所有数据作
                #为数据区域
  \'line\':  {\'color\': \'black\'}, #线条颜色定义为black(黑色)
  \'name\': \'=Sheet1!$A$\'+cur_row, #引用业务名称为图例项
 })
for row in range(2, 7): #数据域以第2～6行进行图表数据系列函数调用
 chart_series(str(row))
chart.set_size({\'width\': 577, \'height\': 287}) #设置图表大小
chart.set_title ({\'name\': u\'爬虫分析\'}) #设置图表（上方）大标题
chart.set_y_axis({\'name\': \'count\'}) #设置y轴（左侧）小标题
worksheet.insert_chart(\'A8\', chart) #在A8单元格插入图表
workbook.close() #关闭Excel文档

由于这里只有一张图片，通过vba 代码很容易生成图片 。方法为，打开该excel 图表，通过alt + F11 快捷键打开宏编辑界面；打开VB编辑器的立即窗口：”视图“-”立即窗口“，或者使用快捷键\”Ctrl + G\” ，接着输入如下代码

activesheet.ChartObjects(1).Chart.Export \"C:\\chart.png\"

按 \” Enter \” 键后，会在C盘生成上面的生成的chart图表。

二、导出多张图表

python代码如下：

#coding: utf-8
import xlsxwriter
workbook = xlsxwriter.Workbook(\'chart_column.xlsx\')
worksheet = workbook.add_worksheet()
bold = workbook.add_format({\'bold\': 1})
# 这是个数据table的列
headings = [\'Number\', \'Batch 1\', \'Batch 2\']
data = [
 [2, 3, 4, 5, 6, 7],
 [10, 40, 50, 20, 10, 50],
 [30, 60, 70, 50, 40, 30],
]
worksheet.write_row(\'A1\', headings, bold)
worksheet.write_column(\'A2\', data[0])
worksheet.write_column(\'B2\', data[1])
worksheet.write_column(\'C2\', data[2])
############################################
#创建一个图表，类型是column
chart1 = workbook.add_chart({\'type\': \'column\'})
# 配置series,这个和前面wordsheet是有关系的。
chart1.add_series({
 \'name\':  \'=Sheet1!$B$1\',
 \'categories\': \'=Sheet1!$A$2:$A$7\',
 \'values\':  \'=Sheet1!$B$2:$B$7\',
})
# Configure a second series. Note use of alternative syntax to define ranges.
chart1.add_series({
 \'name\':  [\'Sheet1\', 0, 2],
 \'categories\': [\'Sheet1\', 1, 0, 6, 0],
 \'values\':  [\'Sheet1\', 1, 2, 6, 2],
})
# Add a chart title and some axis labels.
chart1.set_title ({\'name\': \'Results of sample analysis\'})
chart1.set_x_axis({\'name\': \'Test number\'})
chart1.set_y_axis({\'name\': \'Sample length (mm)\'})
# Set an Excel chart style.
chart1.set_style(11)
# Insert the chart into the worksheet (with an offset).
worksheet.insert_chart(\'D2\', chart1, {\'x_offset\': 25, \'y_offset\': 10})
#######################################################################
#
# Create a stacked chart sub-type.
#
chart2 = workbook.add_chart({\'type\': \'column\', \'subtype\': \'stacked\'})
# Configure the first series.
chart2.add_series({
 \'name\':  \'=Sheet1!$B$1\',
 \'categories\': \'=Sheet1!$A$2:$A$7\',
 \'values\':  \'=Sheet1!$B$2:$B$7\',
})
# Configure second series.
chart2.add_series({
 \'name\':  \'=Sheet1!$C$1\',
 \'categories\': \'=Sheet1!$A$2:$A$7\',
 \'values\':  \'=Sheet1!$C$2:$C$7\',
})
# Add a chart title and some axis labels.
chart2.set_title ({\'name\': \'Stacked Chart\'})
chart2.set_x_axis({\'name\': \'Test number\'})
chart2.set_y_axis({\'name\': \'Sample length (mm)\'})
# Set an Excel chart style.
chart2.set_style(12)
# Insert the chart into the worksheet (with an offset).
worksheet.insert_chart(\'D18\', chart2, {\'x_offset\': 25, \'y_offset\': 10})
#######################################################################
#
# Create a percentage stacked chart sub-type.
#
chart3 = workbook.add_chart({\'type\': \'column\', \'subtype\': \'percent_stacked\'})
# Configure the first series.
chart3.add_series({
 \'name\':  \'=Sheet1!$B$1\',
 \'categories\': \'=Sheet1!$A$2:$A$7\',
 \'values\':  \'=Sheet1!$B$2:$B$7\',
})
# Configure second series.
chart3.add_series({
 \'name\':  \'=Sheet1!$C$1\',
 \'categories\': \'=Sheet1!$A$2:$A$7\',
 \'values\':  \'=Sheet1!$C$2:$C$7\',
})
# Add a chart title and some axis labels.
chart3.set_title ({\'name\': \'Percent Stacked Chart\'})
chart3.set_x_axis({\'name\': \'Test number\'})
chart3.set_y_axis({\'name\': \'Sample length (mm)\'})
# Set an Excel chart style.
chart3.set_style(13)
# Insert the chart into the worksheet (with an offset).
worksheet.insert_chart(\'D34\', chart3, {\'x_offset\': 25, \'y_offset\': 10})
workbook.close()

同一数据源上面创建了三种类型的图 ，由于有三张图，上面的导出一张图的方法肯定是不行了，这里打开宏，创建如下宏内容：

Sub exportimg()
Dim XlsChart As ChartObject
For Each XlsChart In Worksheets(\"Sheet1\").ChartObjects
 XlsChart.Chart.Export Filename:=\"C:\\\" & XlsChart.Name & \".jpg\", FilterName:=\"JPG\"
Next
End Sub

该示例这里就不再截图，具体可以自行运行。