我正在尝试从Android手机上传图像到服务器。这就是我到目前为止所做的事情
OkHttpClient client = new OkHttpClient();
MultipartBuilder builder = new MultipartBuilder();
builder.type(MultipartBuilder.FORM).addPart(RequestBody.create(MediaType.parse("application/json; charset=utf-8"), requestPackage.getJsonParam().toString()));
for (int i = 0; i < requestPackage.getPics().size(); i++) {
builder.addPart(RequestBody.create(MediaType.parse("image/png"/* + i*/), new File(URI.create(requestPackage.getPics().get(i)))));
Log.i("image to upload",URI.create(requestPackage.getPics().get(i)).toString());
}
requestBody = builder.build();
Request request = new Request.Builder().url(requestPackage.getUri()).post(requestBody).build();
try {
response = client.newCall(request).execute();
if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);
// System.out.println(response.body().string());
return response.body().string();
} catch (IOException e) {
e.printStackTrace();
}
如何为不同的部分添加名称。因为如果没有名称（密钥），那么服务器端的人将如何存储它？
答案 0 :(得分：12)
获取OkHttp 2.1，并使用MultipartBuilder.addFormDataPart()，它将文件名作为参数。
答案 1 :(得分：5)
自从之前的答案以来，语法似乎发生了一些变化。我正在使用OkHttp 3.2.0。
public void upload(String url, File file) throws IOException {
RequestBody formBody = new MultipartBody.Builder()
.setType(MultipartBody.FORM)
.addFormDataPart("file", file.getName(),
RequestBody.create(MediaType.parse("image/png"), file))
.addFormDataPart("other_field", "other_field_value")
.build();
Request request = new Request.Builder().url(url).post(formBody).build();
Response response = this.client.newCall(request).execute();
}
答案 2 :(得分：0)
您可以在官方文档中找到所有内容：https://github.com/square/okhttp/wiki/Recipes
特别是你会对Posting a multipart request：
RequestBody requestBody = new MultipartBuilder()
.type(MultipartBuilder.FORM)
.addPart(
Headers.of("Content-Disposition", "form-data; name=\"title\""),
RequestBody.create(null, "Square Logo"))
.addPart(
Headers.of("Content-Disposition", "form-data; name=\"image\""),
RequestBody.create(MEDIA_TYPE_PNG, new File("website/static/logo-square.png")))
.build();
答案 3 :(得分：0)
关于如何使用okhttp3上传文件，这是一个完整的解决方案。 首先，在点击监听器上添加一个带有按钮的文件选择器，如下所示：
用于选择文件的按钮：
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_choose_file:
showFileChooser();
break;
}
}
private String filePath = null;
private File sourceFile;
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityForResult(
Intent.createChooser(intent, "Select a File to Upload"),
FILE_SELECT_CODE);
} catch (android.content.ActivityNotFoundException ex) {
Toast.makeText(this, "Please install a File Manager.",
Toast.LENGTH_SHORT).show();
}
}
然后像这样处理onActivityResult：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case FILE_SELECT_CODE:
if (resultCode == RESULT_OK) {
// Get the Uri of the selected file
Uri uri = data.getData();
File file = new File(getCacheDir(), getFileName(uri));
int maxBufferSize = 1 * 1024 * 1024;
try {
InputStream inputStream = getContentResolver().openInputStream(uri);
Log.e("InputStream Size","Size " + inputStream);
int bytesAvailable = inputStream.available();
int bufferSize = Math.min(bytesAvailable, maxBufferSize);
final byte[] buffers = new byte[bufferSize];
FileOutputStream outputStream = new FileOutputStream(file);
int read = 0;
while ((read = inputStream.read(buffers)) != -1) {
outputStream.write(buffers, 0, read);
}
Log.e("File Size","Size " + file.length());
inputStream.close();
outputStream.close();
file.getPath();
Log.e("File Path","Path " + file.getPath());
file.length();
Log.e("File Size","Size " + file.length());
if(file.length() > 0){
sourceFile = file;
filePath = sourceFile.getPath();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (OutOfMemoryError e) {
e.printStackTrace();
}
} else {
}
break;
}
super.onActivityResult(requestCode, resultCode, data);
}
private String getMimeType(String path) {
FileNameMap fileNameMap = URLConnection.getFileNameMap();
String contentTypeFor = fileNameMap.getContentTypeFor(path);
if (contentTypeFor == null)
{
contentTypeFor = "application/octet-stream";
}
return contentTypeFor;
}
public String getFileName(Uri uri) {
String result = null;
if (uri.getScheme().equals("content")) {
Cursor cursor = getContentResolver().query(uri, null, null, null, null);
try {
if (cursor != null && cursor.moveToFirst()) {
result = cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
}
} finally {
cursor.close();
}
}
if (result == null) {
result = uri.getPath();
int cut = result.lastIndexOf('/');
if (cut != -1) {
result = result.substring(cut + 1);
}
}
return result;
}
最后，处理文件上传以及其他所需的信息，例如：
try {
UpdateInformation("yourEmailAddress", filePath, sourceFile);
} catch (IOException e) {
e.printStackTrace();
}
private void UploadInformation(String email, final String _filePath, final File file) throws IOException {
runOnUiThread(new Runnable() {
@Override
public void run() {
//show progress bar here
}
});
OkHttpClient client = new OkHttpClient.Builder()
.connectTimeout(60, TimeUnit.SECONDS)
.writeTimeout(60, TimeUnit.SECONDS)
.readTimeout(60, TimeUnit.SECONDS)
.build();
String mime = getMimeType(_filePath);
RequestBody body = new MultipartBody.Builder().setType(MultipartBody.FORM)
.addFormDataPart("file", file.getName(),
RequestBody.create(MediaType.parse(mime), file))
.addFormDataPart("email", email)
.build();
okhttp3.Request request = new okhttp3.Request.Builder()
.url("yourEndPointURL")
.post(body)
.addHeader("authorization", "yourEndPointToken")
.addHeader("content-type", "application/json")
.build();
client.newCall(request).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
call.cancel();
runOnUiThread(new Runnable() {
@Override
public void run() {
//hide progress bar here
}
});
}
@Override
public void onResponse(Call call, okhttp3.Response response) throws IOException {
try {
final String myResponse = response.body().string();
runOnUiThread(new Runnable() {
@Override
public void run() {
//hide progress bar here
//Cont from here
//Handle yourEndPoint Response.
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
注意：请不要忘记将此权限添加到清单文件中。
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
答案 4 :(得分：-1)
您可以使用下面的多部分在单个请求中发送多个值
HttpPost httppost = new HttpPost(mPostURL);
MultipartEntity entity = new MultipartEntity();
entity.addPart("value", new StringBody("upload", Charset.forName("UTF-8")));
File myFile = new File(mFilePath);
FileBody fileBody = new FileBody(filePath);
entity.addPart("file", fileBody);
entity.addPart("filename", new StringBody("fileName", Charset.forName("UTF-8")));
httppost.setEntity(entity);
HttpClient httpClient = new DefaultHttpClient();