使用NPOI从Excel中提取图片及图片位置信息-白红宇

使用NPOI从Excel中提取图片及图片位置信息

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发布时间：2019-06-18

本文共 3929 字，大约阅读时间需要 13 分钟。

原文:

问题背景：

话说，在的开发过程中，有一个比较棘手的问题：怎么复制图片呢？

当然，解决这个问题的第一步是：能使用NPOI提取到图片及图片的位置信息。到这里，一切想法都很顺利。但NPOI到底怎么提取图片及图片的位置信息呢？NPOI能不能提取到图片的位置信息呢？

这是两个问题。是两个让BaiGoogleDu几近沉默的问题。但官方教程的评论中还是流露出了答案的蛛丝马迹。

哇咔咔，这是我去看源码寻答案的的动力。

此处省去（N多字）… …，这里宕掉了我三个晚上的时间。

不再累述，代码你懂的… ….

PicturesInfo.cs

public class PicturesInfo
{
public int MinRow { get;set; }
public int MaxRow { get;set; }
public int MinCol { get;set; }
public int MaxCol { get;set; }
public Byte[] PictureData { get; private set; }
 
public PicturesInfo(int minRow, int maxRow, int minCol, int maxCol,Byte[] pictureData)
{
this.MinRow = minRow;
this.MaxRow = maxRow;
this.MinCol = minCol;
this.MaxCol = maxCol;
this.PictureData = pictureData;
}
}

NpoiExtend.cs

public static class NpoiExtend
{
public static List
        GetAllPictureInfos(this ISheet sheet)
{
return sheet.GetAllPictureInfos(null,null,null,null);
}
 
public static List
        GetAllPictureInfos(this ISheet sheet,int? minRow,int? maxRow,int? minCol,int? maxCol,bool onlyInternal = true)
{
if (sheet is HSSFSheet)
{
return GetAllPictureInfos((HSSFSheet)sheet,minRow,maxRow,minCol,maxCol,onlyInternal);
}
else if (sheet is XSSFSheet)
{
return GetAllPictureInfos((XSSFSheet)sheet, minRow, maxRow, minCol, maxCol, onlyInternal);
}
else
{
throw new Exception("未处理类型，没有为该类型添加：GetAllPicturesInfos()扩展方法！");
}
}
 
private static List
        GetAllPictureInfos(HSSFSheet sheet,int? minRow, int? maxRow, int? minCol, int? maxCol, bool onlyInternal)
{
List
        picturesInfoList = new List
        ();
 
var shapeContainer = sheet.DrawingPatriarch as HSSFShapeContainer;
if (null != shapeContainer)
{
var shapeList = shapeContainer.Children;
foreach (var shape in shapeList)
{
if (shape is HSSFPicture && shape.Anchor is HSSFClientAnchor)
{
var picture = (HSSFPicture)shape;
var anchor = (HSSFClientAnchor)shape.Anchor;
if (IsInternalOrIntersect(minRow, maxRow, minCol, maxCol, anchor.Row1, anchor.Row2, anchor.Col1, anchor.Col2, onlyInternal))
{
picturesInfoList.Add(new PicturesInfo(anchor.Row1, anchor.Row2, anchor.Col1, anchor.Col2, picture.PictureData.Data));
}
}
}
}
 
return picturesInfoList;
}
 
private static List
        GetAllPictureInfos(XSSFSheet sheet, int? minRow, int? maxRow, int? minCol, int? maxCol, bool onlyInternal)
{
List
        picturesInfoList = new List
        ();
 
var documentPartList = sheet.GetRelations();
foreach (var documentPart in documentPartList)
{
if (documentPart is XSSFDrawing)
{
var drawing = (XSSFDrawing)documentPart;
var shapeList = drawing.GetShapes();
foreach (var shape in shapeList)
{
if (shape is XSSFPicture)
{
var picture = (XSSFPicture)shape;
var anchor = picture.GetPreferredSize();
if (IsInternalOrIntersect(minRow, maxRow, minCol, maxCol, anchor.Row1, anchor.Row2, anchor.Col1, anchor.Col2, onlyInternal))
{
picturesInfoList.Add(new PicturesInfo(anchor.Row1, anchor.Row2, anchor.Col1, anchor.Col2, picture.PictureData.Data));
}
}
}
}
}
 
return picturesInfoList;
}
 
private static bool IsInternalOrIntersect(int? rangeMinRow, int? rangeMaxRow, int? rangeMinCol, int? rangeMaxCol,
int pictureMinRow, int pictureMaxRow, int pictureMinCol, int pictureMaxCol, bool onlyInternal)
{
int _rangeMinRow = rangeMinRow ?? pictureMinRow;
int _rangeMaxRow = rangeMaxRow ?? pictureMaxRow;
int _rangeMinCol = rangeMinCol ?? pictureMinCol;
int _rangeMaxCol = rangeMaxCol ?? pictureMaxCol;
 
if (onlyInternal)
{
return (_rangeMinRow <= pictureMinRow && _rangeMaxRow >= pictureMaxRow &&
_rangeMinCol <= pictureMinCol && _rangeMaxCol >= pictureMaxCol);
}
else
{
return ((Math.Abs(_rangeMaxRow - _rangeMinRow) + Math.Abs(pictureMaxRow - pictureMinRow) >= Math.Abs(_rangeMaxRow + _rangeMinRow - pictureMaxRow - pictureMinRow)) &&
(Math.Abs(_rangeMaxCol - _rangeMinCol) + Math.Abs(pictureMaxCol - pictureMinCol) >= Math.Abs(_rangeMaxCol + _rangeMinCol - pictureMaxCol - pictureMinCol)));
}
}
}