如何使用python将excel图表保存为图片？

Question

我目前正试图使用win32com python库打开一个包含图表的excel文件，并将该图表保存为同一目录下的图片。

我尝试了下面的代码。

import win32com.client as win32
from win32com.client import Dispatch
import os


xlApp = win32.gencache.EnsureDispatch('Excel.Application')

# Open the workbook with the correct path
workbook = xlApp.Workbooks.Open("C:\\Users\\Owner\\PycharmProjects\\venv\\automaticexcelgrapherv4\\saveImageTest.xlsx")
xlApp.Sheets("Sheet1").Select()
xlApp.Visible = True

xlSheet1 = workbook.Sheets(1)

#Ensure to save any work before running script
xlApp.DisplayAlerts = False

i = 0
for chart in xlSheet1.ChartObjects():

    chart.CopyPicture()
    #Create new temporary sheet
    xlApp.ActiveWorkbook.Sheets.Add(After=xlApp.ActiveWorkbook.Sheets(1)).Name="temp_sheet" + str(i)
    temp_sheet = xlApp.ActiveSheet

    #Add chart object to new sheet.
    cht = xlApp.ActiveSheet.ChartObjects().Add(0,0,800, 600)
    #Paste copied chart into new object
    cht.Chart.Paste()
    #Export image
    #IMP: The next line exports the png image to the new sheet, however I would like to save it in the directory instead
    cht.Chart.Export("chart" + str(i) + ".png")
    i = i+1

xlApp.ActiveWorkbook.Close()
#Restore default behaviour
xlApp.DisplayAlerts = True

这将在excel文件中创建一个新的工作表 并将图表的.png图片放在里面。但是，我不知道如何再将该图片保存在该目录中。

Answer 1

导入后可以尝试用存储。

images = {}
with open(chartOne.png', 'rb') as x:
    image = x.read()
    images['MyImages'] = image

Answer 2

找到了一些类似的代码，经过一些修正后，就成功了。

import win32com.client
import PIL
from PIL import ImageGrab, Image
import os
import sys

inputExcelFilePath = "C:\\Users\\Owner\\PycharmProjects\\venv\\automaticexcelgrapherv4\\saveImageTest.xlsx"
outputPNGImagePath = "C:\\Users\\Owner\\PycharmProjects\\venv\\automaticexcelgrapherv4\\PreviewGraphAutomaticExcelGrapher.png"

# This function extracts a graph from the input excel file and saves it into the specified PNG image path (overwrites the given PNG image)
def saveExcelGraphAsPNG(inputExcelFilePath, outputPNGImagePath):
    # Open the excel application using win32com
    o = win32com.client.Dispatch("Excel.Application")
    # Disable alerts and visibility to the user
    o.Visible = 0
    o.DisplayAlerts = 0
    # Open workbook
    wb = o.Workbooks.Open(inputExcelFilePath)

    # Extract first sheet
    sheet = o.Sheets(1)
    for n, shape in enumerate(sheet.Shapes):
        # Save shape to clipboard, then save what is in the clipboard to the file
        shape.Copy()
        image = ImageGrab.grabclipboard()
        # Saves the image into the existing png file (overwriting) TODO ***** Have try except?
        image.save(outputPNGImagePath, 'png')
        pass
    pass

    wb.Close(True)
    o.Quit()

saveExcelGraphAsPNG(inputExcelFilePath, outputPNGImagePath)

这个函数输入的是一个包含一个图表的excel文件的路径（或者多个，在这种情况下，它会选择最后一个）和一个现有的PNG图片的路径，然后覆盖它，把图表放在里面。