DxFileInput.ValidateByAcceptedFileTypes Property

Specifies whether the component validates files against accepted file types before uploading them.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.2.dll

NuGet Package: DevExpress.Blazor

Declaration

[DefaultValue(true)]
[Parameter]
public bool ValidateByAcceptedFileTypes { get; set; }

Property Value

Type	Default	Description
Boolean	true	true to validate files against accepted file types; otherwise, false.

Remarks

You can use the following APIs to specify file types and extensions accepted by File Input.

Open File Dialog Filter

The AcceptedFileTypes property sets the file type filter in the Open File dialog. The property value is passed to the accept attribute of the underlying input HTML element.

If a user removes the filter, the Open File dialog displays all file types and users can select files that do not match AcceptedFileTypes.

A user can also skip the Open File dialog and simply drop files onto the drop zone.

File Type Validation

Once a file is added to the file list, the component validates the following:

• Whether the file MIME type is in AcceptedFileTypes. To skip MIME type validation, set ValidateByAcceptedFileTypes to false.
• Whether the file name extension is in AllowedFileExtensions.

If validation fails, the File Input cannot upload the file and displays an error message.

Example

The following example disables MIME type validation (ValidateByAcceptedFileTypes is false). In this case, the AcceptedFileTypes property only specifies a filter for the Open File dialog.

<DxFileInput FilesUploading="OnFilesUploading"
             AcceptedFileTypes="@(new List<string> { "image/*", "application/pdf"})"
             ValidateByAcceptedFileTypes="false"/>

@code {
    async Task OnFilesUploading(FilesUploadingEventArgs args) {
        foreach (var file in args.Files) {
            /* The following code is intended for demonstration purposes only.
            Do not read a stream directly in memory to avoid performance and security-related issues. */
            using var stream = new System.IO.MemoryStream();
            await file.OpenReadStream(file.Size).CopyToAsync(stream);
        }
    }
}