如何将图像保存到数据库 [英] How to save images into Database

问题描述

我想知道是否有一种方法可以将图片（.gif类型）保存到sqllite数据库。如果是，我的 DatabaseAdapter 应该如何。

同样是性能问题吗？

解决方案

您应该在数据库中使用 BLOB ：

检查本教程 ...

但我认为你应该下载和存储图像在HashMap，这将使它更简单。

代码：

Stroring

  Map< String，byte []> hh = new HashMap< String，byte []>（）; 
 
 String hi =http://i.stack.imgur.com/TLjuP.jpg; 
 byte [] logoImagedata = getLogoImage（hi）; 
 
 hh.put（img，logoImagedata）; 
  

检索

  byte [] imageByteArray = hh.get（img）; 
 
 ByteArrayInputStream imageStream = new ByteArrayInputStream（imageByteArray）; 
 Bitmap theImage = BitmapFactory.decodeStream（imageStream）; 
  

getLogoImage（）

  private byte [] getLogoImage（String url）{
 try {
 URL imageUrl = new URL（url）; 
 URLConnection ucon = imageUrl.openConnection（）; 
 
 InputStream is = ucon.getInputStream（）; 
 BufferedInputStream bis = new BufferedInputStream（is）; 
 
 ByteArrayBuffer baf = new ByteArrayBuffer（500）; 
 int current = 0; 
 while（（current = bis.read（））！= -1）{
 baf.append（（byte）current）; 
} 
 
 return baf.toByteArray（）; 
} catch（Exception e）{
 Log.d（ImageManager，Error：+ e.toString（））; 
 return null; 
} 
 
} 
  

希望它能帮助你。 p>

I'd like to know if there's a way to save Images (of the type .gif) to the sqllite-database. If yes how should my DatabaseAdapter look like.

Also is there a performance issue?

解决方案

You should use BLOB in your database:

Check this tutorial...

But I think you should download and store image in HashMap, which will make it simpler.

Code:

Stroring

Map<String, byte[]> hh = new HashMap<String, byte[]>();

 String hi = "http://i.stack.imgur.com/TLjuP.jpg";
          byte[] logoImagedata = getLogoImage(hi);       

hh.put("img",logoImagedata); 

Retrieving

byte[] imageByteArray = hh.get("img");

ByteArrayInputStream imageStream = new ByteArrayInputStream(imageByteArray);
        Bitmap theImage= BitmapFactory.decodeStream(imageStream);

getLogoImage()

private byte[] getLogoImage(String url){
           try {
                   URL imageUrl = new URL(url);
                   URLConnection ucon = imageUrl.openConnection();

                   InputStream is = ucon.getInputStream();
                   BufferedInputStream bis = new BufferedInputStream(is);

                   ByteArrayBuffer baf = new ByteArrayBuffer(500);
                   int current = 0;
                   while ((current = bis.read()) != -1) {
                           baf.append((byte) current);
                   }

                   return baf.toByteArray();
           } catch (Exception e) {
                   Log.d("ImageManager", "Error: " + e.toString());
                   return null;
           }

      }

Hope it helps you.

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