RadBinaryImage cannot display a NULL field

[Miao Weibin]

If the image field is NULL, an error will be got : Unable to cast object of type 'System.DBNull' to type 'System.Byte[]' 

[BaiH]

I'm not very familiar with this control but looking at its documentation it seems that the DataValue property accepts a byte[] (as this is an reference type its value do includes assigning a null value too). However as you may know DBNull is not a null but a completely different type which does not have implicit conversion to byte[] defined. Therefore I do not think this should be supported as in same way you may want to bind the control to a string. ;) Instead you may check if the supplied value is of type DBNull and change it to appropriate empty byte array or null.

--BH

[Miao Weibin]

thanks, BaiH, a NULL field should be cast to null or empty byte[];

[Bruce Lam]

How i can cast object of type 'System.DBNull' to type 'System.Byte[]' “. Please help me . I put RadBinaryImage in ItemTemplate of RadCombobox but in field image of my data have null and image how i can cast. Thanks

[Miao Weibin]

Sorry, maybe CAST is mis-used.

<telerik:RadBinaryImage ID="photoOfUser" Style="float: left;" Width="160px" Height="200px" DataValue='<%#Eval("PHOTO") is DBNull ? null : Eval("PHOTO")%>' AutoAdjustImageControlSize="false" AlternateText="Photo" runat="server"></telerik:RadBinaryImage>

[peter]

Thank you so much Miao Weibin, it worked for me. Again, so much grateful of you!