我想把图片上传到"wwwroot/uploads/img"文件夹,但是我遇到了错误。我写了以下代码:
创建视图:
@model imageuploader.Models.Employee
<form method="post" enctype="multipart/form-data" asp-controller="Employee" asp-action="Create">
<div class="form-group">
<div class="col-md-10">
<input asp-for="FirstName" class="form-control" />
</div>
</div>
<div class="form-group">
<div class="col-md-10">
<input asp-for="LastName" Class="form-control" />
</div>
</div>
<div class="form-group">
<div class="col-md-10">
<input asp-for="ImageName" type="file" Class="form-control" />
</div>
</div>
<div class="form-group">
<div class="col-md-10">
<input type="submit" value="Create" />
</div>
</div>
模型:
public class Employee
{
[Key]
public int ID { get; set; }
[Required]
public string FirstName { get; set; }
[Required]
public string LastName { get; set; }
public string ImageName { get; set; }
}
控制器
private readonly RegisterDBContext _context;
private readonly IHostingEnvironment _appEnvironment;
public EmployeeController(RegisterDBContext context, IHostingEnvironment appEnvironment)
{
_context = context;
_appEnvironment = appEnvironment;
}
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create(Employee emp)
{
if (ModelState.IsValid)
{
var files = HttpContext.Request.Form.Files;
foreach (var Image in files)
{
if (Image != null && Image.Length > 0)
{
var file = Image;
//There is an error here
var uploads = Path.Combine(_appEnvironment.WebRootPath, "uploads\\img");
if (file.Length > 0)
{
var fileName = Guid.NewGuid().ToString().Replace("-", "") + Path.GetExtension(file.FileName);
using (var fileStream = new FileStream(Path.Combine(uploads, fileName), FileMode.Create))
{
await file.CopyToAsync(fileStream);
emp.BookPic = fileName;
}
}
}
}
_context.Add(emp);
await _context.SaveChangesAsync();
return RedirectToAction("Index");
}
else
{
var errors = ModelState.Values.SelectMany(v => v.Errors);
}
return View(emp);
}
当我点击提交按钮时,会收到一个错误(错误行已标记),如何将图像或文件上传到指定路径?
错误:
NullReferenceException: Object reference not set to an instance of an object.
imageuploader.Controllers.EmployeeController+<Create>d__2.MoveNext() in EmployeeController.cs
var uploads = Path.Combine(_appEnvironmen.WebRootPath, "uploads\\img\\");
如何在指定路径正确上传图片?
_appEnvironment
?它是NULL
吗? - ShyjuHomeController
中崩溃。但是你说你正在向EmployeeController
发布。如果你的控制器有构造函数来初始化从注入的IHostingEnvironment
实现中的_appEnvironment
变量,它将不会是NULL
。 - Shyju