Java 如何通过HSSF工作簿设置图像大小
我想使用ApachePOI在excel工作簿中插入图像,但无法设置图像的大小。我写了这段代码,但它不是我想要的Java 如何通过HSSF工作簿设置图像大小,java,apache-poi,Java,Apache Poi,我想使用ApachePOI在excel工作簿中插入图像,但无法设置图像的大小。我写了这段代码,但它不是我想要的 InputStream inputStream2=new FileInputStream("C:\\Users\\ftk1187\\Desktop\\tec.png"); byte[] imageBytes2 = IOUtils.toByteArray(inputStream2); int pictureureIdx2 = wb.addPic
InputStream inputStream2=new FileInputStream("C:\\Users\\ftk1187\\Desktop\\tec.png");
byte[] imageBytes2 = IOUtils.toByteArray(inputStream2);
int pictureureIdx2 = wb.addPicture(imageBytes2, Workbook.PICTURE_TYPE_PNG);
inputStream2.close();
CreationHelper helper2 = wb.getCreationHelper();
Drawing drawing2 = sheet.createDrawingPatriarch();
ClientAnchor anchor2 = helper2.createClientAnchor();
anchor2.setDx1(0);
anchor2.setDy1(0);
anchor2.setDx2(100);
anchor2.setDy2(120);
anchor2.setCol1(8);
anchor2.setRow1(1);
Picture pict2 = drawing2.createPicture(anchor2, pictureureIdx2);
pict2.resize(2);
它可以缩放图像,但我想用厘米调整它的大小。我查看了一些论坛,但没有找到任何解决此问题的方法。我还想把这张照片和单元格的中间对齐。下一步我可以试试什么?这并不像你想象的那么简单。不仅有许多不同的测量单位需要考虑,不幸的是,二进制
*.xls
和Office Open XML
*.xlsx
文件格式之间也存在很大的差异
这里使用的最佳测量单位是像素。可以使用单位将其转换为EMU
。每像素EMU
。因此,与其以厘米为单位调整图片大小,不如以像素为单位。但可以使用以下公式将厘米转换为像素:
float pixels = cm / 2.54f * 72f * Units.PIXEL_DPI / Units.POINT_DPI
也就是说:1英寸=2.54厘米,因此厘米/2.54是英寸,英寸*72是点,点*pixel DPI/点DPI是像素
如果我们需要使用像素,并希望将图片水平和垂直放置在单元格的中心位置,当然我们还需要以像素为单位的单元格宽度和行高度。有了这个,我们可以计算图片在单元格上的水平和垂直起始和结束位置。然后我们可以将图片的定位点设置为从单元格左上角开始,加上水平开始位置和垂直开始位置。另外,图片的锚定端位于单元格左上角加上水平端位置和加上垂直端位置
下面的完整示例将图片水平和垂直放置在单元格B2
的中心,大小为3 cm x 1.5 cm,高度为100磅,宽度为50个默认字符。它适用于HSSF
以及XSSF
import java.io.InputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi.util.IOUtils;
import org.apache.poi.util.Units;
class CreateExcelPictureOverCell {
public static void main(String[] args) throws Exception {
Workbook workbook = new HSSFWorkbook(); String filePath = "./Excel.xls";
//Workbook workbook = new XSSFWorkbook(); String filePath = "./Excel.xlsx";
Sheet sheet = workbook.createSheet();
Row row = sheet.createRow(1); // row 2
float rowHeightInPoints = 100f;
row.setHeightInPoints(rowHeightInPoints);
float rowHeightInPixels = rowHeightInPoints * Units.PIXEL_DPI / Units.POINT_DPI;
Cell cell = row.createCell(1); // col B
sheet.setColumnWidth(1, 50*256); // 50 default characters width
float colWidthInPixels = sheet.getColumnWidthInPixels(1);
InputStream inputStream = new FileInputStream("./logo.png");
byte[] imageBytes = IOUtils.toByteArray(inputStream);
int pictureureIdx = workbook.addPicture(imageBytes, Workbook.PICTURE_TYPE_PNG);
inputStream.close();
CreationHelper helper = workbook.getCreationHelper();
Drawing drawing = sheet.createDrawingPatriarch();
ClientAnchor anchor = helper.createClientAnchor();
//set start position of picture's anchor to top left B2
anchor.setRow1(1);
anchor.setCol1(1);
//create picture
Picture pict = drawing.createPicture(anchor, pictureureIdx);
//get picture's original size
int pictOriginalWidthInPixels = pict.getImageDimension().width;
int pictOriginalHeightInPixels = pict.getImageDimension().height;
//set picture's wanted size
float pictWidthInCm = 3f;
float pictWidthInPixels = pictWidthInCm / 2.54f * 72f * Units.PIXEL_DPI / Units.POINT_DPI;
//want scaling in aspect ratio?
//float scale = pictWidthInPixels / pictOriginalWidthInPixels;
//float pictHeightInPixels = pictOriginalHeightInPixels * scale;
//want explicit set height too?
float pictHeightInCm = 1.5f;
float pictHeightInPixels = pictHeightInCm / 2.54f * 72f * Units.PIXEL_DPI / Units.POINT_DPI;
//calculate the horizontal center position
int horCenterPosInPixels = Math.round(colWidthInPixels/2f - pictWidthInPixels/2f);
//set the horizontal center position as Dx1 of anchor
if (workbook instanceof XSSFWorkbook) {
anchor.setDx1(horCenterPosInPixels * Units.EMU_PER_PIXEL); //in unit EMU for XSSF
} else if (workbook instanceof HSSFWorkbook) {
//see https://stackoverflow.com/questions/48567203/apache-poi-xssfclientanchor-not-positioning-picture-with-respect-to-dx1-dy1-dx/48607117#48607117 for HSSF
int DEFAULT_COL_WIDTH = 10 * 256;
anchor.setDx1(Math.round(horCenterPosInPixels * Units.DEFAULT_CHARACTER_WIDTH / 256f * 14.75f * DEFAULT_COL_WIDTH / colWidthInPixels));
}
//calculate the vertical center position
int vertCenterPosInPixels = Math.round(rowHeightInPixels/2f - pictHeightInPixels/2f);
//set the vertical center position as Dy1 of anchor
if (workbook instanceof XSSFWorkbook) {
anchor.setDy1(Math.round(vertCenterPosInPixels * Units.EMU_PER_PIXEL)); //in unit EMU for XSSF
} else if (workbook instanceof HSSFWorkbook) {
//see https://stackoverflow.com/questions/48567203/apache-poi-xssfclientanchor-not-positioning-picture-with-respect-to-dx1-dy1-dx/48607117#48607117 for HSSF
float DEFAULT_ROW_HEIGHT = 12.75f;
anchor.setDy1(Math.round(vertCenterPosInPixels * Units.PIXEL_DPI / Units.POINT_DPI * 14.75f * DEFAULT_ROW_HEIGHT / rowHeightInPixels));
}
//set end position of picture's anchor to top left B2
anchor.setRow2(1);
anchor.setCol2(1);
//calculate the horizontal end position of picture
int horCenterEndPosInPixels = Math.round(horCenterPosInPixels + pictWidthInPixels);
//set the horizontal end position as Dx2 of anchor
if (workbook instanceof XSSFWorkbook) {
anchor.setDx2(horCenterEndPosInPixels * Units.EMU_PER_PIXEL); //in unit EMU for XSSF
} else if (workbook instanceof HSSFWorkbook) {
//see https://stackoverflow.com/questions/48567203/apache-poi-xssfclientanchor-not-positioning-picture-with-respect-to-dx1-dy1-dx/48607117#48607117 for HSSF
int DEFAULT_COL_WIDTH = 10 * 256;
anchor.setDx2(Math.round(horCenterEndPosInPixels * Units.DEFAULT_CHARACTER_WIDTH / 256f * 14.75f * DEFAULT_COL_WIDTH / colWidthInPixels));
}
//calculate the vertical end position of picture
int vertCenterEndPosInPixels = Math.round(vertCenterPosInPixels + pictHeightInPixels);
//set the vertical end position as Dy2 of anchor
if (workbook instanceof XSSFWorkbook) {
anchor.setDy2(Math.round(vertCenterEndPosInPixels * Units.EMU_PER_PIXEL)); //in unit EMU for XSSF
} else if (workbook instanceof HSSFWorkbook) {
//see https://stackoverflow.com/questions/48567203/apache-poi-xssfclientanchor-not-positioning-picture-with-respect-to-dx1-dy1-dx/48607117#48607117 for HSSF
float DEFAULT_ROW_HEIGHT = 12.75f;
anchor.setDy2(Math.round(vertCenterEndPosInPixels * Units.PIXEL_DPI / Units.POINT_DPI * 14.75f * DEFAULT_ROW_HEIGHT / rowHeightInPixels));
}
FileOutputStream out = new FileOutputStream(filePath);
workbook.write(out);
out.close();
workbook.close();
}
}
这有用吗?