本文实例为大家分享了ASP.NET Core实现文件上传和下载的具体代码，供大家参考，具体内容如下
一、文件上传
1.1 获取文件后缀
/// <summary>
/// 获取文件后缀
/// </summary>
/// <param name="fileName">文件名称</param>
/// <returns></returns>
public async static Task<string> GetFileSuffixAsync(string fileName)
{
return await Task.Run(() =>
{
string suffix = Path.GetExtension(fileName);
return suffix;
});
}1.2 上传单文件
public class FileMessage
{
/// <summary>
/// 原文件名称
/// </summary>
public string FileName { get; set; }
/// <summary>
/// 附件名称(协议或其他要进行数据库保存与模型绑定的命名)
/// </summary>
public string ArgumentName { get; set; }
/// <summary>
/// 文件大小(KB)
/// </summary>
public string FileSize { get; set; }
/// <summary>
/// -1：上传失败 0：等待上传 1：已上传
/// </summary>
public int FileStatus { get; set; }
/// <summary>
/// 上传结果
/// </summary>
public string UploadResult { get; set; }
/// <summary>
/// 创建实例
/// </summary>
/// <param name="fileName">原文件名称</param>
/// <param name="argumentName">(新)附件名称</param>
/// <param name="fileSize">大小</param>
/// <param name="fileStatus">文件状态</param>
/// <returns></returns>
public static FileMessage CreateNew(string fileName,
string argumentName,
string fileSize,
int fileStatus,
string uploadResult)
{
return new FileMessage()
{
FileName = fileName,
ArgumentName = argumentName,
FileSize = fileSize,
FileStatus = fileStatus,
UploadResult = uploadResult
};
}
}/// <summary>
/// 上传文件
/// </summary>
/// <param name="file">上传的文件</param>
/// <param name="fold">要存储的文件夹</param>
/// <returns></returns>
public async static Task<FileMessage> UploadFileAsync(IFormFile file, string fold)
{
string fileName = file.FileName;
string path = Directory.GetCurrentDirectory() + @"/Upload/" + fold + "/";
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
string argumentName = DateTime.Now.ToString("yyyyMMddHHmmssfff") + await GetFileSuffixAsync(file.FileName);
string fileSize = Math.Round((decimal)file.Length / 1024, 2) + "k";
string filePath = Path.Combine(path, argumentName);
try
{
using (FileStream stream = new FileStream(filePath, FileMode.Create))
{
await file.CopyToAsync(stream);
}
return FileMessage.CreateNew(fileName, argumentName, fileSize, 1, "文件上传成功");
}
catch (Exception e)
{
return FileMessage.CreateNew(fileName, argumentName, fileSize, -1, "文件上传失败：" + e.Message);
}
}1.3 上传多文件
/// <summary>
/// 上传多文件
/// </summary>
/// <param name="files">上传的文件集合</param>
/// <param name="fold">要存储的文件夹</param>
/// <returns></returns>
public async static Task<List<FileMessage>> UploadFilesAsync(IFormFileCollection files, string fold)
{
string path = Directory.GetCurrentDirectory() + @"/Upload/" + fold + "/";
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
List<FileMessage> messages = new List<FileMessage>();
foreach (var file in files)
{
string fileName = file.FileName;
string argumentName = DateTime.Now.ToString("yyyyMMddHHmmssfff") + await GetFileSuffixAsync(file.FileName);
string fileSize = Math.Round((decimal)file.Length / 1024, 2) + "k";
string filePath = Path.Combine(path, argumentName);
try
{
using (FileStream stream = new FileStream(filePath, FileMode.Create))
{
await file.CopyToAsync(stream);
}
messages.Add(FileMessage.CreateNew(fileName, argumentName, fileSize, 1, "文件上传成功"));
}
catch (Exception e)
{
messages.Add(FileMessage.CreateNew(fileName, argumentName, fileSize, -1, "文件上传失败，失败原因：" + e.Message));
}
}
return messages;
}[Route("api/[controller]")]
[ApiController]
public class ManageProtocolFileController : ControllerBase
{
private readonly string createName = "";
private readonly IWebHostEnvironment _env;
private readonly ILogger<ManageProtocolFileController> _logger;
public ManageProtocolFileController(IWebHostEnvironment env,
ILogger<ManageProtocolFileController> logger)
{
_env = env;
_logger = logger;
}
/// <summary>
/// 协议上传附件
/// </summary>
/// <param name="file"></param>
/// <returns></returns>
[HttpPost("upload")]
public async Task<FileMessage> UploadProtocolFile([FromForm] IFormFile file)
{
return await UploadFileAsync(file, "ManageProtocol");
}
}二、文件下载
2.1 获取ContentType属性
/// <summary>
/// 获取文件ContentType
/// </summary>
/// <param name="fileName">文件名称</param>
/// <returns></returns>
public async static Task<string> GetFileContentTypeAsync(string fileName)
{
return await Task.Run(() =>
{
string suffix = Path.GetExtension(fileName);
var provider = new FileExtensionContentTypeProvider();
var contentType = provider.Mappings[suffix];
return contentType;
});
}2.2 执行下载
[Route("api/[controller]")]
[ApiController]
public class ManageProtocolFileController : ControllerBase
{
private readonly string createName = "";
private readonly IWebHostEnvironment _env;
private readonly ILogger<ManageProtocolFileController> _logger;
public ManageProtocolFileController(IWebHostEnvironment env,
ILogger<ManageProtocolFileController> logger)
{
_env = env;
_logger = logger;
}
/// <summary>
/// 下载附件
/// </summary>
/// <param name="fileName">文件名称</param>
/// <returns></returns>
[HttpGet("download")]
public async Task<FileStreamResult> Download([FromQuery] string fileName)
{
try
{
string rootPath = _env.ContentRootPath + @"/Upload/ManageProtocolFile";
string filePath = Path.Combine(rootPath, fileName);
var stream = System.IO.File.OpenRead(filePath);
string contentType = await GetFileContentTypeAsync(fileName);
_logger.LogInformation("用户:" + createName + "下载后台客户协议附件:" + request.FileName);
return File(stream, contentType, fileName);
}
catch (Exception e)
{
_logger.LogError(e, "用户:" + createName + "下载后台客户协议附件出错，出错原因:" + e.Message);
throw new Exception(e.ToString());
}
}
}以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
