验证一个或另一个

Question

I've created a javascript function that allows me to validate if one field or the other is filled (called, shockingly enough, oneortheother). Essentially, it checks if neither is filled, or both, and throws an error.

One of the fields being validated is a input type="file" field. I'm displaying below the field the existing file, so that the users can see if it's the file they want.

Is there any way to still validate via oneortheother without having a value in the input type="file"? Any kind of javascript trickery?

I'm at wits end at this point, and have a demo later today that needs this functionality, so any help would be greatly appreciated.

EDIT:

As requested, here's some examples:

<label for="pdf">Upload PDF:
<span class="fieldnote">Files of type .pdf</span>
</label>
<input type="file" name="pdf" id="pdf" class="external_form_field oneortheother_url" value="/downloads/white_papers/HigherOrderPerl.pdf"  />
<label>Existing file:</label><span class="preview"><a href="/downloads/white_papers/HigherOrderPerl.pdf" target="_blank">HigherOrderPerl.pdf</a></span>
<label for="url">Link to asset:</label>
<input type="text" name="url" id="url" class="external_form_field oneortheother_pdf" value=""  size="25" />

Notice that the class oneortheother_url and oneortheother_pdf are applied. This allows the validation routine to know which field to compare to. The comparison is:

if (fObj.value && fObj2.value) { }

and

if (!fObj.value && !fObj2.value) { }

Answer 1

I am not sure how your validation function works, but it seems like you could add a hidden input that holds the url of the uploaded preview file OR the value in the file input. Then you could just compare the url input with the hidden input.

But it seems likely you'll just need to write a custom validation function.