It is known to browsers than when doing a postback, we are loosing the file upload control data (the full path of the file the user wanted to upload). This is a situation which may happen when a validation triggers on the server forcing a postback to the client. I do that when the upload control(s) are combined with textbox fields as well as other fields. If the validation fails, everything is shown as is to the user except the full path of the file on the file upload control(s). So, when this is the case, the user has to select the file(s) he/she wanted to upload.
Based on that, many would prefer to separate the file upload support from other fields. So, this will diminish the possibilities of having a fail at the validation level.
While searching for something else, I discovered that page today:
http://www.ironspeed.com/articles/Maintain%20File%20Upload%20Control/Article.aspxThe guy has found a trick to somewhat keep the file name which were uploaded. But, this is not technically a full way of keeping the data as there is no way of bouncing back the data into a file upload control for security reasons. Has anyone, except for highly sophisticated controls such as the Facebook multiple upload control, succeeded to bypass that security by the use of a regular file upload control?