# Upload/Download

### Introduction

This sample demonstrates how to use the upload and download interfaces to upload and download files.

![](screenshots/devices/index.png)

### Concepts

**Upload and download**

  Transfer files from a mobile phone to a remote server and vice versa.

### Required Permissions

The following permission must be declared in the **config.json** file:

"reqPermissions": [{"name": "ohos.permission.INTERNET"}]

### Usage Guidelines

1. Start the application and request for access to the remote server. A list of files on the remote server will be displayed. Select the file to download and click **download**. The file on the remote server is downloaded to the mobile phone, and the download progress is displayed.

2. Tap **next** to go to the upload page, and tap **upload**. The local file is uploaded to the remote server, and the upload progress is displayed.

### Constraints

1. This sample can only be run on standard-system devices.

2. This sample requires DevEco Studio 3.0 Beta4 (Build Version: 3.0.0.992, built on July 14, 2022) to compile and run.

3. HTTPS is supported by default. To support HTTP, you need to add the **network** field to the **config.json** file, and set the **cleartextTraffic** attribute to **true**, that is:
"deviceConfig": {
    "default": {
        "network": {
            "cleartextTraffic": true
        }
    }
}

# 上传下载

### 介绍

 上传就是将文件从本地设备传送至远程服务器，下载是将文件从远程服务器传送至本地设备存储，该示例使用上传下载的接口实现文件的上传下载。

使用方法：

1.启动应用，获取权限后系统会访问远程服务器，将远程服务器的文件列表显示，选择要下载到本机的文件，点击**点击下载**按钮，远端服务器的文件就会下载到本机，文件的下载进度下方会显示。

2.点击下一页，页面会跳转到上传页面，点击**点击上传**按钮，本机的文件会上传至远端服务器，上传进度下方会显示。

### 效果预览

![](screenshots/devices/index.png)

### 相关权限

网络相关权限：ohos.permission.INTERNET

### 依赖
依赖于[上传下载服务器](https://gitee.com/adslk/application_server/tree/master/UploadDownloadServer)才能实现具体的上传下载功能。

### 约束与限制

1.本示例仅支持标准系统上运行。

2.本示例需要使用DevEco Studio 3.0 Beta4 (Build Version: 3.0.0.992, built on July 14, 2022)才可编译运行。

3.默认支持https，如果要支持http，需要在config.json里增加network标签，属性标识 "cleartextTraffic": true。即：

```
"deviceConfig": {
    "default": {
        "network": {
            "cleartextTraffic": true
        }
    }
}
```