issue with the input tag

Saeed Pooladzadeh 221 Reputation points


I need to import an image in my Blazor web assembly app. I have tested and read a lot of content from the web and AI.
But I don't know why none of my input tags are working!

<InputFile @OnChange="HandleFileUpload" />
<input type="file" @onchange="HandleFileUpload" />
<input type="file" @onchange="HandleFileUpload" />
private async Task HandleFileUpload(InputFileChangeEventArgs e)
        var file = e.File;
        var buffer = new byte[file.Size];
        await file.OpenReadStream().ReadAsync(buffer);

        // Send the image to DeepAI for processing
        var generatedAvatar = await GenerateAvatar(buffer);

        // Display the generated avatar
        avatarUrl = $"data:image/png;base64,{Convert.ToBase64String(generatedAvatar)}";
        isImageUploaded = true;
        isAvatarGenerated = true;

Please guide me.


A set of technologies in the .NET Framework for building web applications and XML web services.
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A free and open-source web framework that enables developers to create web apps using C# and HTML being developed by Microsoft.
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2 answers

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  1. Ping Ni-MSFT 490 Reputation points Microsoft Vendor

    Hi @Saeed Pooladzadeh,

    You could F12 in the browser and check the Console panel to see the exception:

    No parameterless constructor defined for type 'namespace.Index'

    So just add the constructor:

    @code {
        public Index()
        public Index(HttpClient httpClient) {
           this.httpClient = httpClient; 

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  2. Saeed Pooladzadeh 221 Reputation points

    But why does it need a parameterless constructor?

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