Question

I’ve been struggling to find some way to do my required conditional binding.

I want to use Eval("products_image") in conditional binding in such a way that if product_image exists in images directory then it’s ok, otherwise it should display “noimage.jpg”.

I tried to do it this way:

<%# (File.Exists(("ProductImages/"+Convert.ToString(Eval("products_image"))))) ? ("ProductImages/"+Convert.ToString(Eval("products_image"))) : "ProductImages/noimage_small.jpg" ; %>

I have tried other ways as well, but every time, I mess up with a bunch of errors.

Can anyone guide me the right way to do this?

Answer 1

<%# (File.Exists(("ProductImages/"+Convert.ToString(Eval("products_image"))))) ? ("ProductImages/"+Convert.ToString(Eval("products_image"))) : "ProductImages/noimage_small.jpg" ; %>

Quite long and unreadable, isn’t it?

I’d suggest adding a method to your code behind or in a <script> tag

// returns the imageFile parameter if the file exists, the defaultFile parameter otherwise
string ImageFileExists(string imageFile, string defaultFile) {
    if (File.Exists(Server.MapPath(imageFile)))
        return imageFile;
    else
        return defaultFile;
}

And then you’d simply use

<%# ImageFileExists("ProductImages/" + Eval("products_image").ToString(), "ProductImages/noimage_small.jpg") %>

Note that I’ve added a Server.MapPath call to the method so that File.Exists will actually look in the right place.