Android 图片传输到服务器与取回

1、将图片转换成字节数组，再转换成字符串

private String getBitmapStr(Bitmap bitmap){

String bitmapStr = null;
try {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream);
byteArrayOutputStream.close();

byte[] buffer = byteArrayOutputStream.toByteArray();

bitmapStr = Base64.encodeToString(buffer,0,buffer.length,Base64.DEFAULT);

} catch (IOException e) {
e.printStackTrace();
}

return bitmapStr;
}

2、从服务器取回图片的字符串数据时，转换字节数组，再转换成bitmap

public Bitmap getBitmap(){
Bitmap bitmap = null;
try{
byte[] pictureBitmap = Base64.decode(picture,Base64.DEFAULT);<span style="white-space:pre"> </span>//picture为返回的图片字符串

for(int i=0; i<pictureBitmap.length; i++) {
if (pictureBitmap[i] < 0) {
pictureBitmap[i] += 256;
}
}
bitmap = BitmapFactory.decodeByteArray(pictureBitmap, 0, pictureBitmap.length);

}catch(Exception e){
e.printStackTrace();
}

return bitmap;
}