如何上传图片到服务器android?

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我想知道哪种上传图像到服务器的最佳方式,而不会影响其质量。我搜索了谷歌搜索发现的各种发布数据的方法。但我不确定哪一个最适合上传。我碰到:

  1. 多部分图片上传。
  2. 使用字节数组上传图像
  3. 使用base64编码的字符串上传图像。

如果图像分辨率太高,我尝试使用Base64编码,导致它出现OOM(内存不足)。

提问于
用户回答回答于

主要活动课采取挑选和上传:

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.MediaStore;
//import android.util.Base64;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import java.io.ByteArrayOutputStream;
import java.util.ArrayList;


public class MainActivity extends Activity {

    Button btpic, btnup;
    private Uri fileUri;
    String picturePath;
    Uri selectedImage;
    Bitmap photo;
    String ba1;
    public static String URL = "Paste your URL here";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btpic = (Button) findViewById(R.id.cpic);
        btpic.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                clickpic();
            }
        });

        btnup = (Button) findViewById(R.id.up);
        btnup.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                upload();
            }
        });
    }

    private void upload() {
        // Image location URL
        Log.e("path", "----------------" + picturePath);

        // Image
        Bitmap bm = BitmapFactory.decodeFile(picturePath);
        ByteArrayOutputStream bao = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG, 90, bao);
        byte[] ba = bao.toByteArray();
       //ba1 = Base64.encodeBytes(ba);

        Log.e("base64", "-----" + ba1);

        // Upload image to server
        new uploadToServer().execute();

    }

    private void clickpic() {
        // Check Camera
        if (getApplicationContext().getPackageManager().hasSystemFeature(
                PackageManager.FEATURE_CAMERA)) {
            // Open default camera
            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

            // start the image capture Intent
            startActivityForResult(intent, 100);

        } else {
            Toast.makeText(getApplication(), "Camera not supported", Toast.LENGTH_LONG).show();
        }
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == 100 && resultCode == RESULT_OK) {

            selectedImage = data.getData();
            photo = (Bitmap) data.getExtras().get("data");

            // Cursor to get image uri to display

            String[] filePathColumn = {MediaStore.Images.Media.DATA};
            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            picturePath = cursor.getString(columnIndex);
            cursor.close();

            Bitmap photo = (Bitmap) data.getExtras().get("data");
            ImageView imageView = (ImageView) findViewById(R.id.Imageprev);
            imageView.setImageBitmap(photo);
        }
    }

    public class uploadToServer extends AsyncTask<Void, Void, String> {

        private ProgressDialog pd = new ProgressDialog(MainActivity.this);
        protected void onPreExecute() {
            super.onPreExecute();
            pd.setMessage("Wait image uploading!");
            pd.show();
        }

        @Override
        protected String doInBackground(Void... params) {

            ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
            nameValuePairs.add(new BasicNameValuePair("base64", ba1));
            nameValuePairs.add(new BasicNameValuePair("ImageName", System.currentTimeMillis() + ".jpg"));
            try {
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost(URL);
                httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpResponse response = httpclient.execute(httppost);
                String st = EntityUtils.toString(response.getEntity());
                Log.v("log_tag", "In the try Loop" + st);

            } catch (Exception e) {
                Log.v("log_tag", "Error in http connection " + e.toString());
            }
            return "Success";

        }

        protected void onPostExecute(String result) {
            super.onPostExecute(result);
            pd.hide();
            pd.dismiss();
        }
    }
}

PHP代码来处理上传图像,并从base64编码数据创建图像:

<?php
error_reporting(E_ALL);
if(isset($_POST['ImageName'])){
$imgname = $_POST['ImageName'];
$imsrc = base64_decode($_POST['base64']);
$fp = fopen($imgname, 'w');
fwrite($fp, $imsrc);
if(fclose($fp)){
 echo "Image uploaded";
}else{
 echo "Error uploading image";
}
}
?>
用户回答回答于
Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");
startActivityForResult(photoPickerIntent, 1);

上面的代码从图库中选择图像:

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == 1)
        if (resultCode == Activity.RESULT_OK) {
            Uri selectedImage = data.getData();

            String filePath = getPath(selectedImage);
            String file_extn = filePath.substring(filePath.lastIndexOf(".") + 1);
            image_name_tv.setText(filePath);

            try {
                if (file_extn.equals("img") || file_extn.equals("jpg") || file_extn.equals("jpeg") || file_extn.equals("gif") || file_extn.equals("png")) {
                    //FINE
                } else {
                    //NOT IN REQUIRED FORMAT
                }
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
}

public String getPath(Uri uri) {
    String[] projection = {MediaColumns.DATA};
    Cursor cursor = managedQuery(uri, projection, null, null, null);
    column_index = cursor
            .getColumnIndexOrThrow(MediaColumns.DATA);
    cursor.moveToFirst();
    imagePath = cursor.getString(column_index);

    return cursor.getString(column_index);
}

现在使用多点形式数据发布数据:

HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("LINK TO SERVER");

多部分表格数据:

MultipartEntity mpEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
if (filePath != null) {
    File file = new File(filePath);
    Log.d("EDIT USER PROFILE", "UPLOAD: file length = " + file.length());
    Log.d("EDIT USER PROFILE", "UPLOAD: file exist = " + file.exists());
    mpEntity.addPart("avatar", new FileBody(file, "application/octet"));
}

最终发布数据到服务器:

httppost.setEntity(mpEntity);
HttpResponse response = httpclient.execute(httppost);

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