CODEWITHSUNDEEP
c#
Vicky
Vicky

Reputation: 829

Check the uri is valid

Uri myuri = new Uri("https://buffalousercontent.blob.core.windows.net/371-static/profileimages/full/39398");

This is my uri, when u hit means it receives image based on user some user doesn't contains image at that time it receives error page.

How to check the received one is image or something in C# code?

Upvotes: 0

Views: 1273

Answers (6)

John Koerner
John Koerner

Reputation: 38079

You can use the Azure client API to do this. Add a reference to Microsoft.WindowsAzure.StorageClient:

    bool IsBlobJpeg(string blobUri)
    {
        try
        {
            Microsoft.WindowsAzure.StorageClient.CloudBlob blob =
                new CloudBlob(
                    blobUri);
            blob.FetchAttributes();
            return (blob.Properties.ContentType == "image/jpeg");

        }
        catch (StorageClientException ex)
        {
            Console.WriteLine(String.Format("{0} Does not exist", blobUri));
            return false;
        }
    }

Upvotes: 0

Chris Hinton
Chris Hinton

Reputation: 866

As mentioned in the other answers, you can look at the content type of the response, or you could try to create an image from the URI.

try {
    var client = new WebClient();
    var image = Image.FromStream(client.OpenRead(uri));
}
catch(ArguementException e) {
    // this exception will be thrown if the URI doesn't point to a valid image.
}

Upvotes: 1

dav_i
dav_i

Reputation: 28097

Well a Uri object itself doesn't know what will happen when you use it as the address of a GET request.

To check if a string is a valid Uri, you can use

Uri uri;
bool valid = Uri.TryCreate(stringInput, UriKind.Absolute, out uri);

To check what the file type of a request is

using (var client = new HttpClient())
{
    var response = client.GetAsync(uri).Result;

    var contentType = response.Content.Headers.ContentType;
}

Upvotes: 0

Chris
Chris

Reputation: 3338

Do a httprequest and check if the response contenttype equals "image/". This function should do the trick!

Boolean IsImageUrl(string URL)
{
    var req = (HttpWebRequest)HttpWebRequest.Create(URL);
    req.Method = "HEAD";
    using (var resp = req.GetResponse())
    {
        return resp.ContentType.ToLower(CultureInfo.InvariantCulture)
                   .StartsWith("image/");
    }
}

Upvotes: 0

Andrew Whitaker
Andrew Whitaker

Reputation: 126042

If you're just looking to validate that the URL contains an image:

bool ValidateImage(string url)
{
    HttpWebRequest r = (HttpWebRequest)WebRequest.Create(url);

    r.Method = "GET";

    try
    {
        HttpWebResponse resp = (HttpWebResponse)r.GetResponse();

        if (resp.ContentType == "image/jpeg")
        {
            Console.WriteLine("Image retrieved successfully.");
            // Process image
            return true;
        }
        else 
        {
            Console.WriteLine("Unable to retrieve image");
        }
    }
    catch
    {
        Console.WriteLine("Unable to retrieve image.");
    }

    return false;
}

Obviously, change the ContentType check to whatever makes sense for your application. You could also use HEAD as the request method (as in @Chris' answer) if you're just looking to validate the content type and not download the entire image right then.

Upvotes: 2

artragis
artragis

Reputation: 3713

To check if there is an error, you have to send a request and then receive an error or a good blob.

To send a request, you can use WebClient as described here :

public bool CheckUri(Uri uri){
   using(var client = new WebClient()){

   try{
        client.DownloadFile(uri);
        return true;
    }catch{//error detected
     return false;
   }
  }
 }

Upvotes: 0

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