Checking filename length in File Browse item before uploading

Question

I have a File Browse item from which users can upload files into the database. Within APEX, the file metadata and content first get uploaded into the view WWV_FLOW_FILES. By design apparently, the underlying table for this view has a NAME field which is limited to 90 characters. I would like to test the length of the Name field and provide a warning to the user if the name exceeds 90 characters, but any validation I write to that effect does not "fire" until after the file has been uploaded to the WWV_FLOW_FILES view. That attempt to upload apparently is the first thing that happens when you Submit with a File Browse item, even before the validation. If the name of the file exceeds 90 characters in length, the attempted upload errors out with a generic Page Not Found error. Is there any way to capture the length of the Name of the file with a File Browse item prior to the attempt to upload to the WWV_FLOW_FILES view, or is my only option just to put a warning banner on the page?

Answer 1

Hello Mike,
>> Column NAME in WWV_FLOW_FILES is VARCHAR2(90). It does not include the local filename path. It include a prefix like "F1521676842/" in the front of the filename.
Yes, you are correct. I spoke from memory, and it seems that I remembered one of my customized tables, where I also save the local full path of the file.
As far as I can see in my system, the extension of the ‘F123….’ is not with a fix length, and the highest one is 18 characters long. Therefore, it seems that the actual file name should be less than 70 characters long.
A similar code to the following can be used in a validation check:
<script type="text/javascript">
function checkFileName(pThis){
  if (pThis.value != "") {
     //get path value (including file name)
     var fileAndPath = pThis.value;
     //find the index of the last "\"
     var lastPathDelimiter = fileAndPath.lastIndexOf("\\");
    //get everything after the last "\"
    var fileNameOnly = fileAndPath.substring(lastPathDelimiter+1);
    if (fileNameOnly.length >70) {
      alert("File name " + fileNameOnly +
          " is too long (" + fileNameOnly.length + " characters).");
      pThis.focus();
</script>The “HTML Form Element Attributes” of the item should include:
onblur=" checkFileName(this)"
Regards,
Arie.