how to set the file size limit in razor pages?

Question

I create UploadImage.cshtml and OnPostUploadImageAsync

the Request.Form.Files is exception:

Multipart body length limit 16384 exceeded.

I set the opt:

builder.Services.AddRazorPages(options =>
{
options.Conventions.AddPageApplicationModelConvention("/Manage/ImageUpload", x => { x.Filters.Add(new RequestFormLimitsAttribute() { MultipartBodyLengthLimit = 268435456 }); });

and the

builder.Services.Configure<Microsoft.AspNetCore.Http.Features.FormOptions>(x =>
{

x.ValueLengthLimit = 268435456;
x.MultipartBodyLengthLimit = 268435456;

});

and [RequestFormLimits(MultipartBodyLengthLimit = 268435456)]

but still the exception.

Answer 1

Hi @mc

I am not hosting iis but hosting dotnet run.

You are using Kestrel, so you need to configure request body limit on Kestrel, code like this:

builder.WebHost.ConfigureKestrel(opt =>
{
    opt.Limits.MaxRequestBodySize=null;  //disable the request body limit.
});

Then, configure the FormOptions as below:

builder.Services.Configure<FormOptions>(options =>
{
    options.ValueLengthLimit = int.MaxValue;
    options.MultipartBodyLengthLimit = int.MaxValue; 
}); 

In the Razor page Post method, get the upload file from the IFormCollection, instead of using IFormFile and model binding.

    public class FileUploadModel : PageModel
    {
        private IWebHostEnvironment _environment;
        public FileUploadModel(IWebHostEnvironment environment)
        {
            _environment = environment;
        }
 

        [RequestFormLimits(MultipartBodyLengthLimit = 268435456)] 
        public async Task OnPostAsync([FromForm] IFormCollection formData)
        {
            var file = formData.Files["file"];
            if (file != null && file.Length > 0)
            {
                var filePath = Path.Combine(_environment.WebRootPath, "uploads", file.FileName);
                using (var stream = new FileStream(filePath, FileMode.Create))
                {
                    await file.CopyToAsync(stream);
                }
            }

        }
    }

The Razor page as below: without using model binding, just using an input file element.

@page
@model RazorWebApp.Pages.FileUploadModel
 
<form method="post" enctype="multipart/form-data">
    <input id="file" type="file" name="file" />
    <input type="submit" />
</form>

The result as below: the upload file size 197MB.

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Best regards,

Dillion

Answer 2

If hosting with IIS you must also set its max limit

<system.webServer>
 <security>
   <requestFiltering>
     <requestLimits maxAllowedContentLength="268435456" />
   </requestFiltering>
 </security>
</system.webServer>