Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");
startActivityForResult(photoPickerIntent, 1);

上述代码用于从库中选择图像

@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);
}

现在使用多部分表单数据发布数据

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

多部分表单数据

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"));
}

最终将数据发布到服务器

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

要选取和上载的主活动类

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，也从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";
}
}
?>

使用下面的代码可以帮助您....

BitmapFactory.Options options = new BitmapFactory.Options();

        options.inSampleSize = 4;
        options.inPurgeable = true;
        Bitmap bm = BitmapFactory.decodeFile("your path of image",options);

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        bm.compress(Bitmap.CompressFormat.JPEG,40,baos); 

        // bitmap object

        byteImage_photo = baos.toByteArray();

                    //generate base64 string of image

                   String encodedImage =Base64.encodeToString(byteImage_photo,Base64.DEFAULT);

  //send this encoded string to server

尝试此方法从相机上载图像文件

package com.example.imageupload;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.message.BasicHeader;

public class MultipartEntity implements HttpEntity {

private String boundary = null;

ByteArrayOutputStream out = new ByteArrayOutputStream();
boolean isSetLast = false;
boolean isSetFirst = false;

public MultipartEntity() {
    this.boundary = System.currentTimeMillis() + "";
}

public void writeFirstBoundaryIfNeeds() {
    if (!isSetFirst) {
        try {
            out.write(("--" + boundary + "\r\n").getBytes());
        } catch (final IOException e) {

        }
    }
    isSetFirst = true;
}

public void writeLastBoundaryIfNeeds() {
    if (isSetLast) {
        return;
    }
    try {
        out.write(("\r\n--" + boundary + "--\r\n").getBytes());
    } catch (final IOException e) {

    }
    isSetLast = true;
}

public void addPart(final String key, final String value) {
    writeFirstBoundaryIfNeeds();
    try {
        out.write(("Content-Disposition: form-data; name=\"" + key + "\"\r\n")
                .getBytes());
        out.write("Content-Type: text/plain; charset=UTF-8\r\n".getBytes());
        out.write("Content-Transfer-Encoding: 8bit\r\n\r\n".getBytes());
        out.write(value.getBytes());
        out.write(("\r\n--" + boundary + "\r\n").getBytes());
    } catch (final IOException e) {

    }
}

public void addPart(final String key, final String fileName,
        final InputStream fin) {
    addPart(key, fileName, fin, "application/octet-stream");
}

public void addPart(final String key, final String fileName,
        final InputStream fin, String type) {
    writeFirstBoundaryIfNeeds();
    try {
        type = "Content-Type: " + type + "\r\n";
        out.write(("Content-Disposition: form-data; name=\"" + key
                + "\"; filename=\"" + fileName + "\"\r\n").getBytes());
        out.write(type.getBytes());
        out.write("Content-Transfer-Encoding: binary\r\n\r\n".getBytes());

        final byte[] tmp = new byte[4096];
        int l = 0;
        while ((l = fin.read(tmp)) != -1) {
            out.write(tmp, 0, l);
        }
        out.flush();
    } catch (final IOException e) {

    } finally {
        try {
            fin.close();
        } catch (final IOException e) {

        }
    }
}

public void addPart(final String key, final File value) {
    try {
        addPart(key, value.getName(), new FileInputStream(value));
    } catch (final FileNotFoundException e) {

    }
}

public long getContentLength() {
    writeLastBoundaryIfNeeds();
    return out.toByteArray().length;
}

public Header getContentType() {
    return new BasicHeader("Content-Type", "multipart/form-data; boundary="
            + boundary);
}

public boolean isChunked() {
    return false;
}

public boolean isRepeatable() {
    return false;
}

public boolean isStreaming() {
    return false;
}

public void writeTo(final OutputStream outstream) throws IOException {
    outstream.write(out.toByteArray());
}

public Header getContentEncoding() {
    return null;
}

public void consumeContent() throws IOException,
        UnsupportedOperationException {
    if (isStreaming()) {
        throw new UnsupportedOperationException(
                "Streaming entity does not implement #consumeContent()");
    }
}

public InputStream getContent() throws IOException,
        UnsupportedOperationException {
    return new ByteArrayInputStream(out.toByteArray());
}

}

使用类进行上载

private void doFileUpload(File file_path) {

    Log.d("Uri", "Do file path" + file_path);

    try {

        HttpClient client = new DefaultHttpClient();
        //use your server path of php file
        HttpPost post = new HttpPost(ServerUploadPath);

        Log.d("ServerPath", "Path" + ServerUploadPath);

        FileBody bin1 = new FileBody(file_path);
        Log.d("Enter", "Filebody complete " + bin1);

        MultipartEntity reqEntity = new MultipartEntity();
        reqEntity.addPart("uploaded_file", bin1);
        reqEntity.addPart("email", new StringBody(useremail));

        post.setEntity(reqEntity);
        Log.d("Enter", "Image send complete");

        HttpResponse response = client.execute(post);
        resEntity = response.getEntity();
        Log.d("Enter", "Get Response");
        try {

            final String response_str = EntityUtils.toString(resEntity);
            if (resEntity != null) {
                Log.i("RESPONSE", response_str);
                JSONObject jobj = new JSONObject(response_str);
                result = jobj.getString("ResponseCode");
                Log.e("Result", "...." + result);

            }
        } catch (Exception ex) {
            Log.e("Debug", "error: " + ex.getMessage(), ex);
        }
    } catch (Exception e) {
        Log.e("Upload Exception", "");
        e.printStackTrace();
    }
}

上传服务

<?php
$image_name = $_FILES["uploaded_file"]["name"]; 
$tmp_arr = explode(".",$image_name);
$img_extn = end($tmp_arr);
$new_image_name = 'image_'. uniqid() .'.'.$img_extn;    
$flag=0;                 

if (file_exists("Images/".$new_image_name))
{
           $msg=$new_image_name . " already exists."
           header('Content-type: application/json');        
           echo json_encode(array("ResponseCode"=>"2","ResponseMsg"=>$msg));        
}else{  
move_uploaded_file($_FILES["uploaded_file"]["tmp_name"],"Images/". $new_image_name);
                   $flag = 1;
}   

if($flag == 1){                    
            require 'db.php';   
            $static_url =$new_image_name;
            $conn=mysql_connect($db_host,$db_username,$db_password) or die("unable to connect localhost".mysql_error());
            $db=mysql_select_db($db_database,$conn) or die("unable to select message_app"); 
            $email = "";
            if((isset($_REQUEST['email'])))
            {
                     $email = $_REQUEST['email'];
            }

    $sql ="insert into alert(images) values('$static_url')";

     $result=mysql_query($sql);

     if($result){
    echo json_encode(array("ResponseCode"=>"1","ResponseMsg"=> "Insert data successfully.","Result"=>"True","ImageName"=>$static_url,"email"=>$email));
       } else
       {

         echo json_encode(array("ResponseCode"=>"2","ResponseMsg"=> "Could not insert data.","Result"=>"False","email"=>$email));
        }
}
    else{
    echo json_encode(array("ResponseCode"=>"2","ResponseMsg"=> "Erroe While Inserting Image.","Result"=>"False"));
    }
    ?>

//Kotlin Version

   private fun setImageForUploading (imagePath:String):String{

        val options = BitmapFactory.Options();

        options.inSampleSize = 2
        //options.inPurgeable = true //deprecated

        val bitmap = BitmapFactory.decodeFile(imagePath,options)

        val byteArrayOutPutStream = ByteArrayOutputStream()

        bitmap.compress(Bitmap.CompressFormat.PNG,90,byteArrayOutPutStream)

        // bitmap object
        val byteImagePhoto = byteArrayOutPutStream.toByteArray()

        //generate base64 string of image
        val encodedImage = Base64.encodeToString(byteImagePhoto,Base64.DEFAULT)

        return encodedImage

    }