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Paperclip for asp.net mvc

Is it exists kind of plugin like Paperclip for Rails?

it is really painful to implement own system for uploading files the resize it...

开发者_运维知识库will be cool to have Attribute for model that will get params like so:

Model:

[Paperclip(Sizes={thumb="100x20",big="200x40"},Path="~/public/")]
public string Image{get;set;}

View:

Html.Editor(x=>x.Image)

here is small tutorial for rails.


Looks like this question is pretty old, I've stumbled across it by accident and because it doesn't seem to be answered yet, I decided to bring my 2¢.

I don't know if such plugin exists for ASP.NET but it would be trivially easy to write one:

[AttributeUsage(AttributeTargets.Property)]
public class PaperClipAttribute : Attribute, IMetadataAware
{
    public PaperClipAttribute(string uploadPath, params string[] sizes)
    {
        if (string.IsNullOrEmpty(uploadPath))
        {
            throw new ArgumentException("Please specify an upload path");
        }

        UploadPath = uploadPath;
        Sizes = sizes;
    }

    public string UploadPath { get; private set; }
    public string[] Sizes { get; private set; }

    public void OnMetadataCreated(ModelMetadata metadata)
    {
        metadata.AdditionalValues["PaperClip"] = this;
    }
}

then define a custom model binder for the HttpPostedFileBase type:

public class PaperClipModelBinder : DefaultModelBinder
{
    public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
    {
        var paperClip = bindingContext.ModelMetadata.AdditionalValues["PaperClip"] as PaperClipAttribute;
        if (paperClip == null)
        {
            return base.BindModel(controllerContext, bindingContext);
        }

        var uploadedFile = base.BindModel(controllerContext, bindingContext) as HttpPostedFileBase;
        if (uploadedFile == null)
        {
            return null;
        }

        var uploadPath = controllerContext.HttpContext.Server.MapPath(paperClip.UploadPath);
        if (!Directory.Exists(uploadPath))
        {
            throw new ArgumentException(string.Format("The specified folder \"{0}\" does not exist", uploadPath));
        }
        var sizes =
            (from size in paperClip.Sizes
             let tokens = size.Split('x')
             select new Size(int.Parse(tokens[0]), int.Parse(tokens[1]))
            ).ToArray();

        foreach (var size in sizes)
        {
            var extension = Path.GetExtension(uploadedFile.FileName);
            var outputFilename = Path.Combine(
                uploadPath,
                Path.ChangeExtension(
                    string.Format("image{0}x{1}", size.Width, size.Height),
                    extension
                )
            );
            Resize(uploadedFile.InputStream, outputFilename, size);
        }

        return base.BindModel(controllerContext, bindingContext);
    }

    private void Resize(Stream input, string outputFile, Size size)
    {
        using (var image = Image.FromStream(input))
        using (var bmp = new Bitmap(size.Width, size.Height))
        using (var gr = Graphics.FromImage(bmp))
        {
            gr.CompositingQuality = CompositingQuality.HighSpeed;
            gr.SmoothingMode = SmoothingMode.HighSpeed;
            gr.InterpolationMode = InterpolationMode.HighQualityBicubic;
            gr.DrawImage(image, new Rectangle(0, 0, size.Width, size.Height));
            bmp.Save(outputFile);
        }
    }
}

which will be registered in Application_Start:

protected void Application_Start()
{
    AreaRegistration.RegisterAllAreas();

    RegisterGlobalFilters(GlobalFilters.Filters);
    RegisterRoutes(RouteTable.Routes);
    ModelBinders.Binders[typeof(HttpPostedFileBase)] = new PaperClipModelBinder();
}

and we are pretty much done. All that's left is classic stuff.

View model:

public class MyViewModel
{
    [PaperClip("~/App_Data", "100x20", "200x40", "640x480")]
    [Required(ErrorMessage = "Please select a file to upload")]
    public HttpPostedFileBase Image { get; set; }
}

Controller:

public class HomeController : Controller
{
    public ActionResult Index()
    {
        return View(new MyViewModel());
    }

    [HttpPost]
    public ActionResult Index(MyViewModel model)
    {
        if (!ModelState.IsValid)
        {
            return View(model);
        }
        return Content("thanks for uploading");
    }
}

View:

@model MyViewModel

@using (Html.BeginForm(null, null, FormMethod.Post, new { enctype = "multipart/form-data" }))
{ 
    @Html.LabelFor(x => x.Image)
    <input type="file" name="image" />
    @Html.ValidationMessageFor(x => x.Image)
    <input type="submit" value="Upload" />
}
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