使用volley上传多张图片，一个参数对应多张图片，转载

https://my.oschina.net/u/1177694/blog/491834 原帖地址

而如果使用volley的话，因为请求数据那些都很简便，但遇到上传文件就麻烦那可不好，同时使用多个网络请求类库也是不太建议的。所以这里就给出了一种解决方法，也要借助一个jar包，这里用到的是httpmime(点击下载)，主要用到的是MultipartEntity类，可以对请求参数进行封装。

主要是继承volley的Request类，然后通过使用httpmim的MultipartEntity类对文件参数进行封装，这里实现了一个参数名对应一个文件，

一个参数名对应多个文件，如果还要多个参数名对应多个文件可以自己试着实现一下哈：

package com.android.volley.toolbox;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;

import com.android.volley.AuthFailureError;
import com.android.volley.NetworkResponse;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyLog;
import com.common.utils.CLog;
import com.common.utils.FileUtil;

public class MultipartRequest extends Request<String> {

	private MultipartEntity entity = new MultipartEntity();

	private final Response.Listener<String> mListener;

	private List<File> mFileParts;
	private String mFilePartName;
	private Map<String, String> mParams;
	/**
	 * 单个文件
	 * @param url
	 * @param errorListener
	 * @param listener
	 * @param filePartName
	 * @param file
	 * @param params
	 */
	public MultipartRequest(String url, Response.ErrorListener errorListener,
			Response.Listener<String> listener, String filePartName, File file,
			Map<String, String> params) {
		super(Method.POST, url, errorListener);

		mFileParts = new ArrayList<File>();
		if (file != null) {
			mFileParts.add(file);
		}
		mFilePartName = filePartName;
		mListener = listener;
		mParams = params;
		buildMultipartEntity();
	}
	/**
	 * 多个文件，对应一个key
	 * @param url
	 * @param errorListener
	 * @param listener
	 * @param filePartName
	 * @param files
	 * @param params
	 */
	public MultipartRequest(String url, Response.ErrorListener errorListener,
			Response.Listener<String> listener, String filePartName,
			List<File> files, Map<String, String> params) {
		super(Method.POST, url, errorListener);
		mFilePartName = filePartName;
		mListener = listener;
		mFileParts = files;
		mParams = params;
		buildMultipartEntity();
	}

	private void buildMultipartEntity() {
		if (mFileParts != null && mFileParts.size() > 0) {
			for (File file : mFileParts) {
				entity.addPart(mFilePartName, new FileBody(file));
			}
			long l = entity.getContentLength();
			CLog.log(mFileParts.size()+"个，长度："+l);
		}

		try {
			if (mParams != null && mParams.size() > 0) {
				for (Map.Entry<String, String> entry : mParams.entrySet()) {
					entity.addPart(
							entry.getKey(),
							new StringBody(entry.getValue(), Charset
									.forName("UTF-8")));
				}
			}
		} catch (UnsupportedEncodingException e) {
			VolleyLog.e("UnsupportedEncodingException");
		}
	}

	@Override
	public String getBodyContentType() {
		return entity.getContentType().getValue();
	}

	@Override
	public byte[] getBody() throws AuthFailureError {
		ByteArrayOutputStream bos = new ByteArrayOutputStream();
		try {
			entity.writeTo(bos);
		} catch (IOException e) {
			VolleyLog.e("IOException writing to ByteArrayOutputStream");
		}
		return bos.toByteArray();
	}

	@Override
	protected Response<String> parseNetworkResponse(NetworkResponse response) {
		CLog.log("parseNetworkResponse");
		if (VolleyLog.DEBUG) {
			if (response.headers != null) {
				for (Map.Entry<String, String> entry : response.headers
						.entrySet()) {
					VolleyLog.d(entry.getKey() + "=" + entry.getValue());
				}
			}
		}

		String parsed;
		try {
			parsed = new String(response.data,
					HttpHeaderParser.parseCharset(response.headers));
		} catch (UnsupportedEncodingException e) {
			parsed = new String(response.data);
		}
		return Response.success(parsed,
				HttpHeaderParser.parseCacheHeaders(response));
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see com.android.volley.Request#getHeaders()
	 */
	@Override
	public Map<String, String> getHeaders() throws AuthFailureError {
		VolleyLog.d("getHeaders");
		Map<String, String> headers = super.getHeaders();

		if (headers == null || headers.equals(Collections.emptyMap())) {
			headers = new HashMap<String, String>();
		}

		return headers;
	}

	@Override
	protected void deliverResponse(String response) {
		mListener.onResponse(response);
	}
}