如何从内部存储中选择文档和图像文件并上传到服务器？

Question

我想从内部存储中选择媒体（图像或文档，pdf或docx格式）文件并上传到服务器，并显示媒体文件的缩略图。

Answer 1

此代码有助于从内部存储上载媒体（图像或文档，pdf或docx格式）文件并上传到服务器。

从内部选择文件：

Intent intent = new Intent();
        //sets the select file to all types of files
        intent.setType("*/*");
        //allows to select data and return it
        intent.setAction(Intent.ACTION_GET_CONTENT);
        //starts new activity to select file and return data
        startActivityForResult(Intent.createChooser(intent,"Choose File to Upload.."),PICK_FILE_REQUEST);

从以下位置获取文件：

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(resultCode == Activity.RESULT_OK){
            if(requestCode == PICK_FILE_REQUEST){
                if(data == null){
                    //no data present
                    return;
                }


                Uri selectedFileUri = data.getData();
                selectedFilePath = FilePath.getPath(this,selectedFileUri);
                Log.i(TAG,"Selected File Path:" + selectedFilePath);

                if(selectedFilePath != null && !selectedFilePath.equals("")){
                    tvFileName.setText(selectedFilePath);
                }else{
                    Toast.makeText(this,"Cannot upload file to server",Toast.LENGTH_SHORT).show();
                }
            }
        }
    }

将文件上传到服务器

public int uploadFile(final String selectedFilePath){

        int serverResponseCode = 0;

        HttpURLConnection connection;
        DataOutputStream dataOutputStream;
        String lineEnd = "\r\n";
        String twoHyphens = "--";
        String boundary = "*****";


        int bytesRead,bytesAvailable,bufferSize;
        byte[] buffer;
        int maxBufferSize = 1 * 1024 * 1024;
        File selectedFile = new File(selectedFilePath);


        String[] parts = selectedFilePath.split("/");
        final String fileName = parts[parts.length-1];

        if (!selectedFile.isFile()){
            dialog.dismiss();

            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    tvFileName.setText("Source File Doesn't Exist: " + selectedFilePath);
                }
            });
            return 0;
        }else{
            try{
                FileInputStream fileInputStream = new FileInputStream(selectedFile);
                URL url = new URL(SERVER_URL);
                connection = (HttpURLConnection) url.openConnection();
                connection.setDoInput(true);//Allow Inputs
                connection.setDoOutput(true);//Allow Outputs
                connection.setUseCaches(false);//Don't use a cached Copy
                connection.setRequestMethod("POST");
                connection.setRequestProperty("Connection", "Keep-Alive");
                connection.setRequestProperty("ENCTYPE", "multipart/form-data");
                connection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
                connection.setRequestProperty("uploaded_file",selectedFilePath);

                //creating new dataoutputstream
                dataOutputStream = new DataOutputStream(connection.getOutputStream());

                //writing bytes to data outputstream
                dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
                dataOutputStream.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\""
                        + selectedFilePath + "\"" + lineEnd);

                dataOutputStream.writeBytes(lineEnd);

                //returns no. of bytes present in fileInputStream
                bytesAvailable = fileInputStream.available();
                //selecting the buffer size as minimum of available bytes or 1 MB
                bufferSize = Math.min(bytesAvailable,maxBufferSize);
                //setting the buffer as byte array of size of bufferSize
                buffer = new byte[bufferSize];

                //reads bytes from FileInputStream(from 0th index of buffer to buffersize)
                bytesRead = fileInputStream.read(buffer,0,bufferSize);

                //loop repeats till bytesRead = -1, i.e., no bytes are left to read
                while (bytesRead > 0){
                    //write the bytes read from inputstream
                    dataOutputStream.write(buffer,0,bufferSize);
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable,maxBufferSize);
                    bytesRead = fileInputStream.read(buffer,0,bufferSize);
                }

                dataOutputStream.writeBytes(lineEnd);
                dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);

                serverResponseCode = connection.getResponseCode();
                String serverResponseMessage = connection.getResponseMessage();

                Log.i(TAG, "Server Response is: " + serverResponseMessage + ": " + serverResponseCode);

                //response code of 200 indicates the server status OK
                if(serverResponseCode == 200){
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            tvFileName.setText("File Upload completed.\n\n You can see the uploaded file here: \n\n" + "http://coderefer.com/extras/uploads/"+ fileName);
                        }
                    });
                }

                //closing the input and output streams
                fileInputStream.close();
                dataOutputStream.flush();
                dataOutputStream.close();



            } catch (FileNotFoundException e) {
                e.printStackTrace();
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(NewClassPdf.this,"File Not Found",Toast.LENGTH_SHORT).show();
                    }
                });
            } catch (MalformedURLException e) {
                e.printStackTrace();
                Toast.makeText(NewClassPdf.this, "URL error!", Toast.LENGTH_SHORT).show();

            } catch (IOException e) {
                e.printStackTrace();
                Toast.makeText(NewClassPdf.this, "Cannot Read/Write File!", Toast.LENGTH_SHORT).show();
            }
            dialog.dismiss();
            return serverResponseCode;
        }

    }

此代码帮助我将文件上传到服务器（所有文件）。