Question

我有内容：//图片的URI，我想将其转换为base64。我不知道该怎么做。我在这个问题上苦苦挣扎了2天，所以请解释为什么以及你的解决方案如何运作。

这是我的代码：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(requestCode==123 && resultCode==RESULT_OK) {
        Uri selectedfile = data.getData(); //The uri with the location of the file
        if (selectedfile != null) {
            Log.e("image", selectedfile.toString());
        }
    }
}

请不要关注这篇文章。我真的需要帮助

Answer 1

您可以使用两个步骤来完成。

1- URI到位图转换：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(requestCode==123 && resultCode==RESULT_OK) {
        Uri selectedfile = data.getData(); //The uri with the location of the file
        if (selectedfile != null) {
           Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedfile);
        }
    }
}

2- Bitmap to Base64字符串转换：

ByteArrayOutputStream outputStream = new ByteArrayOutputStream();  
bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);
byte[] byteArray = outputStream.toByteArray();

String encodedString = Base64.encodeToString(byteArray, Base64.DEFAULT);

结果：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(requestCode==123 && resultCode==RESULT_OK) {
        Uri selectedfile = data.getData(); //The uri with the location of the file
        if (selectedfile != null) {
           Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedfile);

           ByteArrayOutputStream outputStream = new ByteArrayOutputStream();  
           bitmap.compress(Bitmap.CompressFormat.PNG, 100, outputStream);
           byte[] byteArray = outputStream.toByteArray();

           //Use your Base64 String as you wish
           String encodedString = Base64.encodeToString(byteArray, Base64.DEFAULT);
        }
    }
}

从Image URI获取base64字符串

1 个答案: