我是做文件上传下载，服务端是java写的，客户端是ios，下载客户端不知道怎么写，谢谢回复，还请帮忙理理思路

	/**
	 * http下载
	 */
	public static boolean httpDownload(String httpUrl, String saveFile) {
		// 下载网络文件
		int bytesum = 0;
		int byteread = 0;

		URL url = null;
		try {
			url = new URL(httpUrl);
		} catch (MalformedURLException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
			return false;
		}
		FileOutputStream fs = null;
		URLConnection conn = null;
		InputStream inStream = null;
		try {
			conn = url.openConnection();
			inStream = conn.getInputStream();
			fs = new FileOutputStream(saveFile);

			byte[] buffer = new byte[1204];
			while ((byteread = inStream.read(buffer)) != -1) {
				bytesum += byteread;
//				System.out.println(bytesum);
				fs.write(buffer, 0, byteread);
			}
			return true;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
			return false;
		} catch (IOException e) {
			e.printStackTrace();
			return false;
		} finally {
			if (null != fs) {
				try {
					fs.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (null != inStream) {
				try {
					inStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}

		}
	}

以上是java实现

搜索 ios http 下载 这是其中一个结果

http://blog.sina.com.cn/s/blog_6ec3c9ce01019bcx.html