Apache Poi Ppt 简明教程
Apache POI PPT - Images
在本章中,您将学习如何向 PPT 添加图像以及如何从中读取图像。
Adding Image
您可以使用 createPicture() 的 XSLFSlide 方法向演示文稿添加图像。此方法以字节数组格式接受图像。因此,您需要创建要添加到演示文稿的图像的字节数组。
按照给定的步骤向演示文稿添加图像。使用 XMLSlideShow 创建一个空幻灯片,如下所示 −
XMLSlideShow ppt = new XMLSlideShow();
在其中使用 createSlide() 创建一个空演示文稿。
XSLFSlide slide = ppt.createSlide();
读取要添加的图像文件,并使用 IOUtils 类的 IOUtils.toByteArray() 将其转换为字节数组,如下所示 −
//reading an image
File image = new File("C://POIPPT//boy.jpg");
//converting it into a byte array
byte[] picture = IOUtils.toByteArray(new FileInputStream(image));
使用 addPicture() 将图像添加到演示文稿。此方法接受两个变量:要添加的图像的字节数组格式和表示图像文件格式的静态变量。 addPicture() 方法的用法如下所示 −
XSLFPictureData idx = ppt.addPicture(picture, XSLFPictureData.PICTURE_TYPE_PNG);
使用 createPicture() 将图像嵌入到幻灯片中,如下所示 −
XSLFPictureShape pic = slide.createPicture(idx);
下面给出了在演示文稿的幻灯片中添加图像的完整程序 −
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.poi.sl.usermodel.PictureData.PictureType;
import org.apache.poi.util.IOUtils;
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.poi.xslf.usermodel.XSLFPictureData;
import org.apache.poi.xslf.usermodel.XSLFPictureShape;
import org.apache.poi.xslf.usermodel.XSLFSlide;
public class AddingImage {
public static void main(String args[]) throws IOException {
//creating a presentation
XMLSlideShow ppt = new XMLSlideShow();
//creating a slide in it
XSLFSlide slide = ppt.createSlide();
//reading an image
File image = new File("C://POIPPT//boy.jpg");
//converting it into a byte array
byte[] picture = IOUtils.toByteArray(new FileInputStream(image));
//adding the image to the presentation
XSLFPictureData idx = ppt.addPicture(picture, PictureType.PNG);
//creating a slide with given picture on it
XSLFPictureShape pic = slide.createPicture(idx);
//creating a file object
File file = new File("addingimage.pptx");
FileOutputStream out = new FileOutputStream(file);
//saving the changes to a file
ppt.write(out);
System.out.println("image added successfully");
out.close();
}
}
将上述 Java 代码另存为 AddingImage.java ,然后从命令提示符编译并执行,如下所示 −
$javac AddingImage.java
$java AddingImage
它将编译和执行以生成以下输出 −
reordering of the slides is done
带有新添加幻灯片的演示文稿(其中包含图像)如下所示 −
Reading Image
您可以使用 XMLSlideShow 类中的 getPictureData() 方法获取所有图片的数据。以下程序从演示文稿读取图像 −
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.poi.sl.usermodel.PictureData.PictureType;
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.poi.xslf.usermodel.XSLFPictureData;
public class Readingimage {
public static void main(String args[]) throws IOException {
//open an existing presentation
File file = new File("addingimage.pptx");
XMLSlideShow ppt = new XMLSlideShow(new FileInputStream(file));
//reading all the pictures in the presentation
for(XSLFPictureData data : ppt.getPictureData()){
byte[] bytes = data.getData();
String fileName = data.getFileName();
PictureType pictureFormat = data.getType();
System.out.println("picture name: " + fileName);
System.out.println("picture format: " + pictureFormat);
}
//saving the changes to a file
FileOutputStream out = new FileOutputStream(file);
ppt.write(out);
out.close();
}
}
将上述 Java 代码另存为 Readingimage.java ,然后从命令提示符编译并执行,如下所示 −
$javac Readingimage.java
$java Readingimage
它将编译和执行以生成以下输出 −
picture name: image1.png
picture format: 6