If the user experiences connection problems while uploading files to the server, these files may be corrupted during transmission. In such situations it would be convenient to check if the received files contain errors. To do that you may use the HashAlgorithm property.

If you specify this property and select at least one algorithm, Image Uploader will calculate hash values for files being uploaded and encode them using the Base64 algorithm. The encoded values will be attached as fields to the POST request. You may specify any combination of the following algorithms - SHA, MD2, and MD5.

On the server side, you should calculate hash value for received files using the same algorithms and compare the result with values sent by Image Uploader. The Robust Upload Sample demonstrates how to do it.